Util (Codename One API)

java.lang.Object
- com.codename1.io.Util

```
public class Util
extends Object
```
Various utility methods used for HTTP/IO operations

Constructor Summary

Constructors
Constructor and Description

Util()

Constructors
Constructor and Description
`Util()`

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static void`	`cleanup(Object o)` Closes the object (connection, stream etc.) without throwing any exception, even if the object is null
`static void`	`copy(InputStream i, OutputStream o)` Copy the input stream into the output stream, closes both streams when finishing or in a case of an exception
`static void`	`copy(InputStream i, OutputStream o, int bufferSize)` Copy the input stream into the output stream, closes both streams when finishing or in a case of an exception
`static void`	`copyNoClose(InputStream i, OutputStream o, int bufferSize)` Copy the input stream into the output stream, without closing the streams when done
`static void`	`copyNoClose(InputStream i, OutputStream o, int bufferSize, IOProgressListener callback)` Copy the input stream into the output stream, without closing the streams when done
`static String`	`decode(String s, String enc, boolean plusToSpace)` Decodes a String URL encoded URL
`static AsyncResource<Image>`	`downloadImageToCache(String url)` Downloads an image to the cache asynchronously.
`static void`	`downloadImageToCache(String url, SuccessCallback<Image> onSuccess, FailureCallback<Image> onFail)` Downloads an image to the cache asynchronously.
`static AsyncResource<Image>`	`downloadImageToFileSystem(String url, String fileName)` Downloads an image to the file system asynchronously.
`static void`	`downloadImageToFileSystem(String url, String fileName, SuccessCallback<Image> onSuccess)` Downloads an image to the file system asynchronously.
`static void`	`downloadImageToFileSystem(String url, String fileName, SuccessCallback<Image> onSuccess, FailureCallback<Image> onFail)` Downloads an image to the file system asynchronously.
`static AsyncResource<Image>`	`downloadImageToStorage(String url, String fileName)` Downloads an image to storage asynchronously.
`static void`	`downloadImageToStorage(String url, String fileName, SuccessCallback<Image> onSuccess)` Downloads an image to storage asynchronously.
`static void`	`downloadImageToStorage(String url, String fileName, SuccessCallback<Image> onSuccess, FailureCallback<Image> onFail)` Downloads an image to storage asynchronously.
`static void`	`downloadUrlSafely(String url, String fileName, OnComplete<Integer> percentageCallback, OnComplete<String> filesavedCallback)` Safely download the given URL to the Storage or to the FileSystemStorage: this method is resistant to network errors and capable of resume the download as soon as network conditions allow and in a completely transparent way for the user; note that in the global network error handling, there must be an automatic
`static boolean`	`downloadUrlToFile(String url, String fileName, boolean showProgress)` Blocking method that will download the given URL to the file system storage and return when the operation completes
`static void`	`downloadUrlToFileSystemInBackground(String url, String fileName)` Non-blocking method that will download the given URL to file system storage in the background and return immediately
`static void`	`downloadUrlToFileSystemInBackground(String url, String fileName, ActionListener onCompletion)` Non-blocking method that will download the given URL to file system storage in the background and return immediately
`static boolean`	`downloadUrlToStorage(String url, String fileName, boolean showProgress)` Blocking method that will download the given URL to storage and return when the operation completes
`static void`	`downloadUrlToStorageInBackground(String url, String fileName)` Non-blocking method that will download the given URL to storage in the background and return immediately.
`static void`	`downloadUrlToStorageInBackground(String url, String fileName, ActionListener onCompletion)` Non-blocking method that will download the given URL to storage in the background and return immediately
`static String`	`encodeBody(byte[] buf)` Deprecated. use encodeUrl(char[]) instead
`static String`	`encodeBody(char[] buf)` Encode a string for HTML post requests matching the style used in application/x-www-form-urlencoded
`static String`	`encodeBody(String str)` Encode a string for HTML post requests matching the style used in application/x-www-form-urlencoded
`static String`	`encodeUrl(byte[] buf)` Deprecated. use encodeUrl(char[]) instead
`static String`	`encodeUrl(char[] buf)` Encode a string for HTML requests
`static String`	`encodeUrl(String str)` Encode a string for HTML requests
`static String`	`encodeUrl(String str, String doNotEncodeChars)` Encodes the provided string as a URL (with %20 for spaces).
`static long`	`getFileSizeWithoutDownload(String url)` Returns -1 if the content length is unknown, a value greater than 0 if the Content-Length is known.
`static long`	`getFileSizeWithoutDownload(String url, boolean checkPartialDownloadSupport)` Returns -2 if the server doesn't accept partial downloads (and if checkPartialDownloadSupport is true), -1 if the content length is unknow, a value greater than 0 if the Content-Length is known.
`static String`	`getIgnorCharsWhileEncoding()` These chars will not be encoded by the encoding method in this class as requested in RFE 427 http://java.net/jira/browse/LWUIT-427
`static String`	`getURLBasePath(String url)` Returns the URL's base path, which is the same as the path only without an ending file e.g.: http://domain.com/f/f.html would return as: /f/
`static String`	`getURLHost(String url)` Returns the URL's host portion
`static String`	`getURLPath(String url)` Returns the URL's path
`static String`	`getURLProtocol(String url)` Returns the protocol of an absolute URL e.g.
`static String`	`getUUID()` Creates a new UUID, that is a 128-bit number used to identify information in computer systems.
`static String`	`getUUID(long time, long clockSeqAndNode)` Creates a custom UUID, from the given two `long` values.
`static String`	`guessMimeType(byte[] data)` Tries to determine the mime type of a byte array based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the `http` server or by the file extension.
`static String`	`guessMimeType(InputStream in)` Tries to determine the mime type of an InputStream based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the `http` server or by the file extension.
`static String`	`guessMimeType(String sourceFile)` Tries to determine the mime type of a file based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the `http` server or by the file extension.
`static int`	`indexOf(Object[] arr, Object value)` Finds the object at the given offset while using the == operator and not the equals method call, it doesn't rely on the ordering of the elements like the Arrays method.
`static void`	`insertObjectAtOffset(Object[] sourceArray, Object[] destinationArray, int offset, Object o)` Inserts the object at the destination array offset
`static boolean`	`instanceofByteArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofDoubleArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofFloatArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofIntArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofLongArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofObjArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static boolean`	`instanceofShortArray(Object o)` Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
`static void`	`mergeArrays(Object[] arr1, Object[] arr2, Object[] destinationArray)` Merges arrays into one larger array
`static int`	`readAll(InputStream i, byte[] b)` Reads until the array is full or until the stream ends
`static void`	`readFully(InputStream i, byte[] b)` The read fully method from data input stream is very useful for all types of streams...
`static void`	`readFully(InputStream i, byte[] b, int off, int len)` The read fully method from data input stream is very useful for all types of streams...
`static byte[]`	`readInputStream(InputStream i)` Converts a small input stream to a byte array
`static Object`	`readObject(DataInputStream input)` Reads an object from the stream, notice that this is the inverse of the `writeObject(java.lang.Object, java.io.DataOutputStream)`.
`static String`	`readToString(File file)` Reads the contents of a file to a string.
`static String`	`readToString(File file, String charset)` Reads the contents of a file to a string.
`static String`	`readToString(InputStream i)` Reads an input stream to a string
`static String`	`readToString(InputStream i, String encoding)` Reads an input stream to a string
`static String`	`readToString(Reader reader)` Reads a reader to a string
`static String`	`readUTF(DataInputStream d)` Reads a UTF string that may be null previously written by writeUTF
`static void`	`register(Externalizable e)` Registers this externalizable so readObject will be able to load such objects.
`static void`	`register(String id, Class c)` Registers this externalizable so readObject will be able to load such objects.
`static String`	`relativeToAbsolute(String baseURL, String relativeURL)` Converts a relative url e.g.: /myfile.html to an absolute url
`static void`	`removeObjectAtOffset(Object[] sourceArray, Object[] destinationArray, int offset)` Removes the object at the source array offset and copies all other objects to the destination array
`static void`	`removeObjectAtOffset(Object[] sourceArray, Object[] destinationArray, Object o)` Removes the object at the source array offset and copies all other objects to the destination array
`static void`	`setDateFormatter(SimpleDateFormat formatter)` Sets a custom formatter to use when toDateValue is invoked
`static void`	`setIgnorCharsWhileEncoding(String s)` These chars will not be encoded by the encoding method in this class as requested in RFE 427 http://java.net/jira/browse/LWUIT-427
`static void`	`setImplementation(CodenameOneImplementation impl)` Invoked internally from Display, this method is for internal use only
`static void`	`sleep(int t)` Shorthand method for Thread sleep that doesn't throw the stupid interrupted checked exception
`static String[]`	`split(String original, String separator)` Provides a utility method breaks a given String to array of String according to the given separator
`static boolean`	`toBooleanValue(Object val)` Returns true or false based on a "soft" object
`static char[]`	`toCharArray(String s)` toCharArray should return a new array always, however some devices might suffer a bug that allows mutating a String (serious security hole in the JVM) hence this method simulates the proper behavior
`static Date`	`toDateValue(Object o)` Tries to convert an arbitrary object to a date
`static double`	`toDoubleValue(Object number)` Returns the number object as a double
`static float`	`toFloatValue(Object number)` Returns the number object as a float
`static int`	`toIntValue(Object number)` Returns the number object as an int
`static long`	`toLongValue(Object number)` Returns the number object as a long
`static void`	`wait(Object o)` Shorthand method wait method that doesn't throw the stupid interrupted checked exception, it also includes the synchronized block to further reduce code clutter
`static void`	`wait(Object o, int t)` Shorthand method wait method that doesn't throw the stupid interrupted checked exception, it also includes the synchronized block to further reduce code clutter
`static void`	`writeObject(Object o, DataOutputStream out)` Writes an object to the given output stream, notice that it should be externalizable or one of the supported types.
`static void`	`writeStringToFile(File file, String contents)` Writes a string to a file using UTF-8 encoding.
`static void`	`writeStringToFile(File file, String contents, String charset)` Writes a string to a file.
`static void`	`writeUTF(String s, DataOutputStream d)` Writes a string with a null flag, this allows a String which may be null
`static String`	`xorDecode(String s)` Encodes a string in a way that makes it harder to read it "as is" this makes it possible for Strings to be "encoded" within the app and thus harder to discover by a casual search.
`static String`	`xorEncode(String s)` The inverse method of xorDecode, this is normally unnecessary and is here mostly for completeness

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Util
```
public Util()
```
- Method Detail
  - setIgnorCharsWhileEncoding
```
public static void setIgnorCharsWhileEncoding(String s)
```
    These chars will not be encoded by the encoding method in this class as requested in RFE 427 http://java.net/jira/browse/LWUIT-427
    
    Parameters:
    
    s - set of characters to skip when encoding
  - getIgnorCharsWhileEncoding
```
public static String getIgnorCharsWhileEncoding()
```
    These chars will not be encoded by the encoding method in this class as requested in RFE 427 http://java.net/jira/browse/LWUIT-427
    
    Returns:
    
    chars skipped
  - copy
```
public static void copy(InputStream i,
                        OutputStream o)
                 throws IOException
```
    Copy the input stream into the output stream, closes both streams when finishing or in a case of an exception
    
    Parameters:
    
    i - source
    
    o - destination
    
    Throws:
    
    IOException
  - copyNoClose
```
public static void copyNoClose(InputStream i,
                               OutputStream o,
                               int bufferSize)
                        throws IOException
```
    Copy the input stream into the output stream, without closing the streams when done
    
    Parameters:
    
    i - source
    
    o - destination
    
    bufferSize - the size of the buffer, which should be a power of 2 large enough
    
    Throws:
    
    IOException
  - copyNoClose
```
public static void copyNoClose(InputStream i,
                               OutputStream o,
                               int bufferSize,
                               IOProgressListener callback)
                        throws IOException
```
    Copy the input stream into the output stream, without closing the streams when done
    
    Parameters:
    
    i - source
    
    o - destination
    
    bufferSize - the size of the buffer, which should be a power of 2 large enough
    
    callback - called after each copy step
    
    Throws:
    
    IOException
  - copy
```
public static void copy(InputStream i,
                        OutputStream o,
                        int bufferSize)
                 throws IOException
```
    Copy the input stream into the output stream, closes both streams when finishing or in a case of an exception
    
    Parameters:
    
    i - source
    
    o - destination
    
    bufferSize - the size of the buffer, which should be a power of 2 large enough
    
    Throws:
    
    IOException
  - cleanup
```
public static void cleanup(Object o)
```
    Closes the object (connection, stream etc.) without throwing any exception, even if the object is null
    
    Parameters:
    
    o - Connection, Stream or other closeable object
  - readToString
```
public static String readToString(InputStream i)
                           throws IOException
```
    Reads an input stream to a string
    
    Parameters:
    
    i - the input stream
    
    Returns:
    
    a UTF-8 string
    
    Throws:
    
    IOException - thrown by the stream
  - readToString
```
public static String readToString(File file,
                                  String charset)
                           throws IOException
```
    Reads the contents of a file to a string.
    
    Parameters:
    
    file - The file to read.
    
    charset - The Charset to use to write the file.
    
    Returns:
    
    The string read from the file.
    
    Throws:
    
    IOException - If the file does not exist, or cannot be read for some reason.
    
    Since:
    
    8.0
  - readToString
```
public static String readToString(File file)
                           throws IOException
```
    Reads the contents of a file to a string. Uses UTF-8 encoding.
    
    Parameters:
    
    file - The file to read.
    
    Returns:
    
    The string read from the file.
    
    Throws:
    
    IOException - If the file does not exist, or cannot be read for some reason.
    
    Since:
    
    8.0
  - writeStringToFile
```
public static void writeStringToFile(File file,
                                     String contents)
                              throws IOException
```
    Writes a string to a file using UTF-8 encoding.
    
    Parameters:
    
    file - The file to write to.
    
    contents - The contents to write to the file.
    
    Throws:
    
    IOException - If it cannot write to the file for some reason.
    
    Since:
    
    8.0
  - writeStringToFile
```
public static void writeStringToFile(File file,
                                     String contents,
                                     String charset)
                              throws IOException
```
    Writes a string to a file.
    
    Parameters:
    
    file - The file to write to.
    
    contents - The contents to write to the file.
    
    charset - The charset to use. If null, it defaults to UTF-8
    
    Throws:
    
    IOException - If it cannot write to the file for some reason.
    
    Since:
    
    8.0
  - readToString
```
public static String readToString(InputStream i,
                                  String encoding)
                           throws IOException
```
    Reads an input stream to a string
    
    Parameters:
    
    i - the input stream
    
    encoding - the encoding of the stream
    
    Returns:
    
    a string
    
    Throws:
    
    IOException - thrown by the stream
  - readToString
```
public static String readToString(Reader reader)
                           throws IOException
```
    Reads a reader to a string
    
    Parameters:
    
    i - the input stream
    
    encoding - the encoding of the stream
    
    Returns:
    
    a string
    
    Throws:
    
    IOException - thrown by the stream
    
    Since:
    
    7.0
  - readInputStream
```
public static byte[] readInputStream(InputStream i)
                              throws IOException
```
    Converts a small input stream to a byte array
    
    Parameters:
    
    i - the stream to convert
    
    Returns:
    
    byte array of the content of the stream
    
    Throws:
    
    IOException
  - register
```
public static void register(Externalizable e)
```
    Registers this externalizable so readObject will be able to load such objects.
    
    The sample below demonstrates the usage and registration of the Externalizable interface:
    
    Parameters:
    
    e - the externalizable instance
  - register
```
public static void register(String id,
                            Class c)
```
    Registers this externalizable so readObject will be able to load such objects.
    
    The sample below demonstrates the usage and registration of the Externalizable interface:
    
    Parameters:
    
    id - id of the externalizable
    
    c - the class for the externalizable
  - writeObject
```
public static void writeObject(Object o,
                               DataOutputStream out)
                        throws IOException
```
    Writes an object to the given output stream, notice that it should be externalizable or one of the supported types.
    
    The sample below demonstrates the usage and registration of the Externalizable interface:
    
    Parameters:
    
    o - the object to write which can be null
    
    out - the destination output stream
    
    Throws:
    
    IOException - thrown by the stream
  - instanceofObjArray
```
public static boolean instanceofObjArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofByteArray
```
public static boolean instanceofByteArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofShortArray
```
public static boolean instanceofShortArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofLongArray
```
public static boolean instanceofLongArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofIntArray
```
public static boolean instanceofIntArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofFloatArray
```
public static boolean instanceofFloatArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - instanceofDoubleArray
```
public static boolean instanceofDoubleArray(Object o)
```
    Deprecated. this method serves as a temporary workaround for an XMLVM bug and will be removed once the bug is fixed
    
    This method allows working around issue 58
    
    Parameters:
    
    o - object to test
    
    Returns:
    
    true if it matches the state
  - readObject
```
public static Object readObject(DataInputStream input)
                         throws IOException
```
    Reads an object from the stream, notice that this is the inverse of the writeObject(java.lang.Object, java.io.DataOutputStream).
    
    The sample below demonstrates the usage and registration of the Externalizable interface:
    
    Parameters:
    
    input - the source input stream
    
    Throws:
    
    IOException - thrown by the stream
  - encodeUrl
```
public static String encodeUrl(String str)
```
    Encode a string for HTML requests
    
    Parameters:
    
    str - none encoded string
    
    Returns:
    
    encoded string
  - encodeUrl
```
public static String encodeUrl(String str,
                               String doNotEncodeChars)
```
    Encodes the provided string as a URL (with %20 for spaces).
    
    Parameters:
    
    str - The URL to encode
    
    doNotEncodeChars - A string whose characters will not be encoded.
    
    Returns:
  - toCharArray
```
public static char[] toCharArray(String s)
```
    toCharArray should return a new array always, however some devices might suffer a bug that allows mutating a String (serious security hole in the JVM) hence this method simulates the proper behavior
    
    Parameters:
    
    s - a string
    
    Returns:
    
    the contents of the string as a char array guaranteed to be a copy of the current array
  - decode
```
public static String decode(String s,
                            String enc,
                            boolean plusToSpace)
```
    Decodes a String URL encoded URL
    
    Parameters:
    
    s - the string
    
    enc - the encoding (defaults to UTF-8 if null)
    
    plusToSpace - true if plus signs be converted to spaces
    
    Returns:
    
    a decoded string
  - encodeBody
```
public static String encodeBody(String str)
```
    Encode a string for HTML post requests matching the style used in application/x-www-form-urlencoded
    
    Parameters:
    
    str - none encoded string
    
    Returns:
    
    encoded string
  - encodeUrl
```
public static String encodeUrl(byte[] buf)
```
    Deprecated. use encodeUrl(char[]) instead
    
    Encode a string for HTML requests
    
    Parameters:
    
    buf - none encoded string
    
    Returns:
    
    encoded string
  - encodeUrl
```
public static String encodeUrl(char[] buf)
```
    Encode a string for HTML requests
    
    Parameters:
    
    buf - none encoded string
    
    Returns:
    
    encoded string
  - encodeBody
```
public static String encodeBody(char[] buf)
```
    Encode a string for HTML post requests matching the style used in application/x-www-form-urlencoded
    
    Parameters:
    
    buf - none encoded string
    
    Returns:
    
    encoded string
  - encodeBody
```
public static String encodeBody(byte[] buf)
```
    Deprecated. use encodeUrl(char[]) instead
    
    Encode a string for HTML post requests matching the style used in application/x-www-form-urlencoded
    
    Parameters:
    
    buf - none encoded string
    
    Returns:
    
    encoded string
  - relativeToAbsolute
```
public static String relativeToAbsolute(String baseURL,
                                        String relativeURL)
```
    Converts a relative url e.g.: /myfile.html to an absolute url
    
    Parameters:
    
    baseURL - a source URL whose properties should be used to construct the actual URL
    
    relativeURL - relative address
    
    Returns:
    
    an absolute URL
  - getURLProtocol
```
public static String getURLProtocol(String url)
```
    Returns the protocol of an absolute URL e.g. http, https etc.
    
    Parameters:
    
    url - absolute URL
    
    Returns:
    
    protocol
  - getURLHost
```
public static String getURLHost(String url)
```
    Returns the URL's host portion
    
    Parameters:
    
    url - absolute URL
    
    Returns:
    
    the domain of the URL
  - getURLPath
```
public static String getURLPath(String url)
```
    Returns the URL's path
    
    Parameters:
    
    url - absolute URL
    
    Returns:
    
    the path within the host
  - getURLBasePath
```
public static String getURLBasePath(String url)
```
    Returns the URL's base path, which is the same as the path only without an ending file e.g.: http://domain.com/f/f.html would return as: /f/
    
    Parameters:
    
    url - absolute URL
    
    Returns:
    
    the path within the host
  - writeUTF
```
public static void writeUTF(String s,
                            DataOutputStream d)
                     throws IOException
```
    Writes a string with a null flag, this allows a String which may be null
    
    Parameters:
    
    s - the string to write
    
    d - the destination output stream
    
    Throws:
    
    IOException
  - readUTF
```
public static String readUTF(DataInputStream d)
                      throws IOException
```
    Reads a UTF string that may be null previously written by writeUTF
    
    Parameters:
    
    d - the stream
    
    Returns:
    
    a string or null
    
    Throws:
    
    IOException
  - readFully
```
public static void readFully(InputStream i,
                             byte[] b)
                      throws IOException
```
    The read fully method from data input stream is very useful for all types of streams...
    
    Parameters:
    
    b - the buffer into which the data is read.
    
    Throws:
    
    IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.
  - readFully
```
public static final void readFully(InputStream i,
                                   byte[] b,
                                   int off,
                                   int len)
                            throws IOException
```
    The read fully method from data input stream is very useful for all types of streams...
    
    Parameters:
    
    b - the buffer into which the data is read.
    
    off - the start offset of the data.
    
    len - the number of bytes to read.
    
    Throws:
    
    IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.
  - readAll
```
public static int readAll(InputStream i,
                          byte[] b)
                   throws IOException
```
    Reads until the array is full or until the stream ends
    
    Parameters:
    
    b - the buffer into which the data is read.
    
    Returns:
    
    the amount read
    
    Throws:
    
    IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.
  - split
```
public static String[] split(String original,
                             String separator)
```
    Provides a utility method breaks a given String to array of String according to the given separator
    
    Parameters:
    
    original - the String to break
    
    separator - the pattern to look in the original String
    
    Returns:
    
    array of Strings from the original String
  - setImplementation
```
public static void setImplementation(CodenameOneImplementation impl)
```
    Invoked internally from Display, this method is for internal use only
    
    Parameters:
    
    impl - implementation instance
  - mergeArrays
```
public static void mergeArrays(Object[] arr1,
                               Object[] arr2,
                               Object[] destinationArray)
```
    Merges arrays into one larger array
  - removeObjectAtOffset
```
public static void removeObjectAtOffset(Object[] sourceArray,
                                        Object[] destinationArray,
                                        Object o)
```
    Removes the object at the source array offset and copies all other objects to the destination array
    
    Parameters:
    
    sourceArray - the source array
    
    destinationArray - the resulting array which should be of the length sourceArray.length - 1
    
    o - the object to remove from the array
  - removeObjectAtOffset
```
public static void removeObjectAtOffset(Object[] sourceArray,
                                        Object[] destinationArray,
                                        int offset)
```
    Removes the object at the source array offset and copies all other objects to the destination array
    
    Parameters:
    
    sourceArray - the source array
    
    destinationArray - the resulting array which should be of the length sourceArray.length - 1
    
    offset - the offset of the array
  - insertObjectAtOffset
```
public static void insertObjectAtOffset(Object[] sourceArray,
                                        Object[] destinationArray,
                                        int offset,
                                        Object o)
```
    Inserts the object at the destination array offset
    
    Parameters:
    
    sourceArray - the source array
    
    destinationArray - the resulting array which should be of the length sourceArray.length + 1
    
    offset - the offset of the array
    
    o - the object
  - indexOf
```
public static int indexOf(Object[] arr,
                          Object value)
```
    Finds the object at the given offset while using the == operator and not the equals method call, it doesn't rely on the ordering of the elements like the Arrays method.
    
    Parameters:
    
    arr - the array
    
    value - the value to search
    
    Returns:
    
    the offset or -1
  - downloadUrlToStorage
```
public static boolean downloadUrlToStorage(String url,
                                           String fileName,
                                           boolean showProgress)
```
    Blocking method that will download the given URL to storage and return when the operation completes
    
    Parameters:
    
    url - the URL
    
    fileName - the storage file name
    
    showProgress - whether to block the UI until download completes/fails
    
    Returns:
    
    true on success false on error
  - downloadUrlToFile
```
public static boolean downloadUrlToFile(String url,
                                        String fileName,
                                        boolean showProgress)
```
    Blocking method that will download the given URL to the file system storage and return when the operation completes
    
    Parameters:
    
    url - the URL
    
    fileName - the file name
    
    showProgress - whether to block the UI until download completes/fails
    
    Returns:
    
    true on success false on error
  - downloadUrlToStorageInBackground
```
public static void downloadUrlToStorageInBackground(String url,
                                                    String fileName)
```
    Non-blocking method that will download the given URL to storage in the background and return immediately. This method can be used to fetch data dynamically and asynchronously e.g. in this code it is used to fetch book covers for the ImageViewer:
    
    Parameters:
    
    url - the URL
    
    fileName - the storage file name
  - downloadUrlToFileSystemInBackground
```
public static void downloadUrlToFileSystemInBackground(String url,
                                                       String fileName)
```
    Non-blocking method that will download the given URL to file system storage in the background and return immediately
    
    Parameters:
    
    url - the URL
    
    fileName - the file name
  - downloadUrlToStorageInBackground
```
public static void downloadUrlToStorageInBackground(String url,
                                                    String fileName,
                                                    ActionListener onCompletion)
```
    Non-blocking method that will download the given URL to storage in the background and return immediately
    
    Parameters:
    
    url - the URL
    
    fileName - the storage file name
    
    onCompletion - invoked when download completes
  - downloadUrlToFileSystemInBackground
```
public static void downloadUrlToFileSystemInBackground(String url,
                                                       String fileName,
                                                       ActionListener onCompletion)
```
    Non-blocking method that will download the given URL to file system storage in the background and return immediately
    
    Parameters:
    
    url - the URL
    
    fileName - the file name
    
    onCompletion - invoked when download completes
  - downloadImageToFileSystem
```
public static void downloadImageToFileSystem(String url,
                                             String fileName,
                                             SuccessCallback<Image> onSuccess,
                                             FailureCallback<Image> onFail)
```
    Downloads an image to the file system asynchronously. If the image is already downloaded it will just load it directly from the file system.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the path to the file where the image should be downloaded. If this file already exists, it will simply load this file and skip the network request altogether.
    
    onSuccess - Callback called on success.
    
    onFail - Callback called if we fail to load the image.
    
    Since:
    
    3.4
    
    See Also:
    
    ConnectionRequest.downloadImageToFileSystem(java.lang.String, com.codename1.util.SuccessCallback, com.codename1.util.FailureCallback)
  - downloadImageToFileSystem
```
public static AsyncResource<Image> downloadImageToFileSystem(String url,
                                                             String fileName)
```
    Downloads an image to the file system asynchronously. If the image is already downloaded it will just load it directly from the file system.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the path to the file where the image should be downloaded. If this file already exists, it will simply load this file and skip the network request altogether.
    
    Since:
    
    7.0
    
    See Also:
    
    ConnectionRequest.downloadImageToFileSystem(java.lang.String, com.codename1.util.SuccessCallback, com.codename1.util.FailureCallback)
  - downloadImageToFileSystem
```
public static void downloadImageToFileSystem(String url,
                                             String fileName,
                                             SuccessCallback<Image> onSuccess)
```
    Downloads an image to the file system asynchronously. If the image is already downloaded it will just load it directly from the file system.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the path to the file where the image should be downloaded. If this file already exists, it will simply load this file and skip the network request altogether.
    
    onSuccess - Callback called on success.
    
    Since:
    
    3.4
    
    See Also:
    
    ConnectionRequest.downloadImageToFileSystem(java.lang.String, com.codename1.util.SuccessCallback)
  - downloadImageToStorage
```
public static void downloadImageToStorage(String url,
                                          String fileName,
                                          SuccessCallback<Image> onSuccess,
                                          FailureCallback<Image> onFail)
```
    Downloads an image to storage asynchronously. If the image is already downloaded it will just load it directly from storage.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the storage file to save the image to. If this file already exists, it will simply load this file and skip the network request altogether.
    
    onSuccess - Callback called on success.
    
    onFail - Callback called if we fail to load the image.
    
    Since:
    
    3.4
    
    See Also:
    
    ConnectionRequest.downloadImageToStorage(java.lang.String, com.codename1.util.SuccessCallback, com.codename1.util.FailureCallback)
  - downloadImageToStorage
```
public static AsyncResource<Image> downloadImageToStorage(String url,
                                                          String fileName)
```
    Downloads an image to storage asynchronously. If the image is already downloaded it will just load it directly from storage.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the storage file to save the image to. If this file already exists, it will simply load this file and skip the network request altogether.
    
    Since:
    
    7.0
    
    See Also:
    
    ConnectionRequest.downloadImageToStorage(java.lang.String, com.codename1.util.SuccessCallback, com.codename1.util.FailureCallback)
  - downloadImageToCache
```
public static void downloadImageToCache(String url,
                                        SuccessCallback<Image> onSuccess,
                                        FailureCallback<Image> onFail)
```
    Downloads an image to the cache asynchronously.
    
    Parameters:
    
    url - The URL to download.
    
    onSuccess - Callback to run on successful completion.
    
    onFail - Callback to run if download fails.
  - downloadImageToCache
```
public static AsyncResource<Image> downloadImageToCache(String url)
```
    Downloads an image to the cache asynchronously.
    
    Parameters:
    
    url - The URL of the image to download.
    
    Returns:
    
    AsyncResource to wrap the Image.
    
    Since:
    
    7.0
  - downloadImageToStorage
```
public static void downloadImageToStorage(String url,
                                          String fileName,
                                          SuccessCallback<Image> onSuccess)
```
    Downloads an image to storage asynchronously. If the image is already downloaded it will just load it directly from storage.
    
    Parameters:
    
    url - The URL to download the image from.
    
    fileName - The the storage file to save the image to. If this file already exists, it will simply load this file and skip the network request altogether.
    
    onSuccess - Callback called on success.
    
    Since:
    
    3.4
    
    See Also:
    
    ConnectionRequest.downloadImageToStorage(java.lang.String, com.codename1.util.SuccessCallback)
  - sleep
```
public static void sleep(int t)
```
    Shorthand method for Thread sleep that doesn't throw the stupid interrupted checked exception
    
    Parameters:
    
    t - the time
  - wait
```
public static void wait(Object o,
                        int t)
```
    Shorthand method wait method that doesn't throw the stupid interrupted checked exception, it also includes the synchronized block to further reduce code clutter
    
    Parameters:
    
    o - the object to wait on
    
    t - the time
  - wait
```
public static void wait(Object o)
```
    Shorthand method wait method that doesn't throw the stupid interrupted checked exception, it also includes the synchronized block to further reduce code clutter
    
    Parameters:
    
    o - the object to wait on
  - toBooleanValue
```
public static boolean toBooleanValue(Object val)
```
    Returns true or false based on a "soft" object
    
    Parameters:
    
    val - a boolean value as a Boolean object, String or number
    
    Returns:
    
    true or false
  - toIntValue
```
public static int toIntValue(Object number)
```
    Returns the number object as an int
    
    Parameters:
    
    number - this can be a String or any number type
    
    Returns:
    
    an int value or an exception
  - toLongValue
```
public static long toLongValue(Object number)
```
    Returns the number object as a long
    
    Parameters:
    
    number - this can be a String or any number type
    
    Returns:
    
    a long value or an exception
  - toFloatValue
```
public static float toFloatValue(Object number)
```
    Returns the number object as a float
    
    Parameters:
    
    number - this can be a String or any number type
    
    Returns:
    
    a float value or an exception
  - toDoubleValue
```
public static double toDoubleValue(Object number)
```
    Returns the number object as a double
    
    Parameters:
    
    number - this can be a String or any number type
    
    Returns:
    
    a double value or an exception
  - setDateFormatter
```
public static void setDateFormatter(SimpleDateFormat formatter)
```
    Sets a custom formatter to use when toDateValue is invoked
    
    Parameters:
    
    formatter - the formatter to use
  - toDateValue
```
public static Date toDateValue(Object o)
```
    Tries to convert an arbitrary object to a date
    
    Parameters:
    
    o - an object that can be a string, number or date
    
    Returns:
    
    a Date object
  - xorDecode
```
public static String xorDecode(String s)
```
    Encodes a string in a way that makes it harder to read it "as is" this makes it possible for Strings to be "encoded" within the app and thus harder to discover by a casual search.
    
    Parameters:
    
    s - the string to decode
    
    Returns:
    
    the decoded string
  - xorEncode
```
public static String xorEncode(String s)
```
    The inverse method of xorDecode, this is normally unnecessary and is here mostly for completeness
    
    Parameters:
    
    s - a regular string
    
    Returns:
    
    a String that can be used in the xorDecode method
  - guessMimeType
```
public static String guessMimeType(String sourceFile)
                            throws IOException
```
    Tries to determine the mime type of a file based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the http server or by the file extension.
    
    Parameters:
    
    sourceFile, - it automatically choose Storage API or FileSystemStorage API
    
    Returns:
    
    the detected mime type, or "application/octet-stream" if the type is not detected
    
    Throws:
    
    IOException
  - guessMimeType
```
public static String guessMimeType(InputStream in)
                            throws IOException
```
    Tries to determine the mime type of an InputStream based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the http server or by the file extension.
    
    Parameters:
    
    in -
    
    Returns:
    
    the detected mime type, or "application/octet-stream" if the type is not detected
    
    Throws:
    
    IOException
  - guessMimeType
```
public static String guessMimeType(byte[] data)
```
    Tries to determine the mime type of a byte array based on its first bytes.Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the http server or by the file extension.
    
    Parameters:
    
    data -
    
    Returns:
    
    the detected mime type, or "application/octet-stream" if the type is not detected
  - getFileSizeWithoutDownload
```
public static long getFileSizeWithoutDownload(String url)
```
    Returns -1 if the content length is unknown, a value greater than 0 if the Content-Length is known.
    
    Parameters:
    
    url -
    
    Returns:
    
    Content-Length if known
  - getFileSizeWithoutDownload
```
public static long getFileSizeWithoutDownload(String url,
                                              boolean checkPartialDownloadSupport)
```
    Returns -2 if the server doesn't accept partial downloads (and if checkPartialDownloadSupport is true), -1 if the content length is unknow, a value greater than 0 if the Content-Length is known.
    
    Parameters:
    
    url -
    
    checkPartialDownloadSupport - if true returns -2 if the server doesn't accept partial downloads.
    
    Returns:
    
    Content-Length if known
  - downloadUrlSafely
```
public static void downloadUrlSafely(String url,
                                     String fileName,
                                     OnComplete<Integer> percentageCallback,
                                     OnComplete<String> filesavedCallback)
                              throws IOException
```
    Safely download the given URL to the Storage or to the FileSystemStorage: this method is resistant to network errors and capable of resume the download as soon as network conditions allow and in a completely transparent way for the user; note that in the global network error handling, there must be an automatic
```
.retry()
```
    , as in the code example below.
    
    This method is useful if the server correctly returns Content-Length and if it supports partial downloads: if not, it works like a normal download.
    
    Pros: always allows you to complete downloads, even if very heavy (e.g. 100MB), even if the connection is unstable (network errors) and even if the app goes temporarily in the background (on some platforms the download will continue in the background, on others it will be temporarily suspended).
    
    Cons: since this method is based on splitting the download into small parts (512kbytes is the default), this approach causes many GET requests that slightly slow down the download and cause more traffic than normally needed.
    
    Usage example:
    Parameters:
    
    url -
    
    fileName - must be a valid Storage file name or FileSystemStorage file path
    
    percentageCallback - invoked (in EDT) during the download to notify the progress (from 0 to 100); it can be null if you are not interested in monitoring the progress
    
    filesavedCallback - invoked (in EDT) only when the download is finished; if null, no action is taken
    
    Throws:
    
    IOException
  - getUUID
```
public static String getUUID()
```
    Creates a new UUID, that is a 128-bit number used to identify information in computer systems. UUIDs aim to be unique for practical purposes.
    
    This implementation uses the system clock and some device info as seeds for random data, that are enough for practical usage. More specifically, two instances of Random, instantiated with different seeds, are used. The first seed corresponds to the timestamp in which the first object of the static class UUID is created, the second seed is a number (long type) that identifies the current installation of the app and is assumed to be as different as possible from other installations of the app. A unique identifier (long type) associated with the current app installation can be specified by the developer via the Preference "CustomDeviceId__$" (as in the following example) BEFORE the generation of the first UIID, or - if it is not specified - it is obtained from an internal Codename One implementation; in the worst case, if an identifier has not been specified by the developer and Codename One is unable to distinguish the current installation of the app from other installations, an internal algorithm will be used that will generate a number based on some hardware and software characteristics of the device: the number thus generated will be the same on identical models of the same device and with the same version of the operating system, but will vary between different models. Even in the worst case scenario, the probability that two app installations with identical device identifiers will generate the first UIID in the same timestamp is very low.
    
    As a tip, consider that any alphanumeric text string (corresponding for example to a username) can be converted into a long type number, considering this string as a number based on 36, provided it does not exceed 12 characters. This suggestion is applied in the following example.
    
    Code example:
    
    Returns:
    
    a pseudo-random Universally Unique Identifier in its canonical textual representation
  - getUUID
```
public static String getUUID(long time,
                             long clockSeqAndNode)
```
    Creates a custom UUID, from the given two long values.
    
    Parameters:
    
    time - the upper 64 bits
    
    clockSeqAndNode - the lower 64 bits
    
    Returns:
    
    a Universally Unique Identifier in its canonical textual representation

Class Util

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Util

Method Detail

setIgnorCharsWhileEncoding

getIgnorCharsWhileEncoding

copy

copyNoClose

copyNoClose

copy

cleanup

readToString

readToString

readToString

writeStringToFile

writeStringToFile

readToString

readToString

readInputStream

register

register

writeObject

instanceofObjArray

instanceofByteArray

instanceofShortArray

instanceofLongArray

instanceofIntArray

instanceofFloatArray

instanceofDoubleArray

readObject

encodeUrl

encodeUrl

toCharArray

decode

encodeBody

encodeUrl

encodeUrl

encodeBody

encodeBody

relativeToAbsolute

getURLProtocol

getURLHost

getURLPath

getURLBasePath

writeUTF

readUTF

readFully

readFully

readAll

split

setImplementation

mergeArrays

removeObjectAtOffset

removeObjectAtOffset

insertObjectAtOffset

indexOf

downloadUrlToStorage

downloadUrlToFile

downloadUrlToStorageInBackground

downloadUrlToFileSystemInBackground

downloadUrlToStorageInBackground

downloadUrlToFileSystemInBackground

downloadImageToFileSystem

downloadImageToFileSystem

downloadImageToFileSystem

downloadImageToStorage

downloadImageToStorage

downloadImageToCache

downloadImageToCache

downloadImageToStorage

sleep

wait

wait

toBooleanValue

toIntValue

toLongValue

toFloatValue