IOUtils (Wicket Parent 8.15.0-SNAPSHOT API)

java.lang.Object
- org.apache.wicket.util.io.IOUtils

```
public final class IOUtils
extends Object
```
General IO Stream manipulation.
This class provides static utility methods for input/output operations.
- closeQuietly - these method closes any kind of closeable resource, e.g. an input/output stream or reader/writer ignoring nulls and exceptions
- toXxx - these methods read data from a stream
- write - these methods write data to a stream
- copy - these methods copy all the data from one stream to another
- contentEquals - these methods compare the content of two streams
The byte-to-char methods and char-to-byte methods involve a conversion step. Two methods are provided in each case, one that uses the platform default encoding and the other which allows you to specify an encoding. You are encouraged to always specify an encoding because relying on the platform default can lead to unexpected results, for example when moving from development to production.
All the methods in this class that read a stream are buffered internally. This means that there is no cause to use a BufferedInputStream or BufferedReader. The default buffer size of 4K has been show to be efficient in tests.
Wherever possible, the methods in this class do not flush or close the stream. This is to avoid making non-portable assumptions about the streams' origin and further use. Thus the caller is still responsible for closing streams after use.
Origin of code: Apache Avalon (Excalibur)
Author:

Peter Donald, Jeff Turner, Matthew Hawthorne, Stephen Colebourne, Gareth Davis

Constructor Summary

Constructors
Constructor and Description

IOUtils()
Instances should NOT be constructed in standard programming.

Constructors
Constructor and Description
`IOUtils()` Instances should NOT be constructed in standard programming.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`close(Closeable closeable)` Closes a closeable.
`static void`	`closeQuietly(Closeable closeable)` Unconditionally close a `Closeable`.
`static boolean`	`contentEquals(InputStream input1, InputStream input2)` Compare the contents of two Streams to determine if they are equal or not.
`static boolean`	`contentEquals(Reader input1, Reader input2)` Compare the contents of two Readers to determine if they are equal or not.
`static int`	`copy(InputStream input, OutputStream output)` Copy bytes from an `InputStream` to an `OutputStream`.
`static void`	`copy(InputStream input, Writer output)` Copy bytes from an `InputStream` to chars on a `Writer` using the default character encoding of the platform.
`static void`	`copy(InputStream input, Writer output, String encoding)` Copy bytes from an `InputStream` to chars on a `Writer` using the specified character encoding.
`static void`	`copy(Reader input, OutputStream output)` Copy chars from a `Reader` to bytes on an `OutputStream` using the default character encoding of the platform, and calling flush.
`static void`	`copy(Reader input, OutputStream output, String encoding)` Copy chars from a `Reader` to bytes on an `OutputStream` using the specified character encoding, and calling flush.
`static int`	`copy(Reader input, Writer output)` Copy chars from a `Reader` to a `Writer`.
`static byte[]`	`toByteArray(InputStream input)` Get the contents of an `InputStream` as a `byte[]`.
`static byte[]`	`toByteArray(Reader input)` Get the contents of a `Reader` as a `byte[]` using the default character encoding of the platform.
`static byte[]`	`toByteArray(Reader input, String encoding)` Get the contents of a `Reader` as a `byte[]` using the specified character encoding.
`static char[]`	`toCharArray(InputStream is)` Get the contents of an `InputStream` as a character array using the default character encoding of the platform.
`static char[]`	`toCharArray(InputStream is, String encoding)` Get the contents of an `InputStream` as a character array using the specified character encoding.
`static char[]`	`toCharArray(Reader input)` Get the contents of a `Reader` as a character array.
`static String`	`toString(InputStream input)` Get the contents of an `InputStream` as a String using the default character encoding of the platform.
`static String`	`toString(InputStream input, String encoding)` Get the contents of an `InputStream` as a String using the specified character encoding.
`static String`	`toString(Reader input)` Get the contents of a `Reader` as a String.
`static void`	`write(byte[] data, OutputStream output)` Writes bytes from a `byte[]` to an `OutputStream`.
`static void`	`write(byte[] data, Writer output)` Writes bytes from a `byte[]` to chars on a `Writer` using the default character encoding of the platform.
`static void`	`write(byte[] data, Writer output, String encoding)` Writes bytes from a `byte[]` to chars on a `Writer` using the specified character encoding.
`static void`	`write(char[] data, OutputStream output)` Writes chars from a `char[]` to bytes on an `OutputStream`.
`static void`	`write(char[] data, OutputStream output, String encoding)` Writes chars from a `char[]` to bytes on an `OutputStream` using the specified character encoding.
`static void`	`write(char[] data, Writer output)` Writes chars from a `char[]` to a `Writer` using the default character encoding of the platform.
`static void`	`write(StringBuilder data, OutputStream output)` Writes chars from a `AppendingStringBuffer` to bytes on an `OutputStream` using the default character encoding of the platform.
`static void`	`write(StringBuilder data, OutputStream output, String encoding)` Writes chars from a `AppendingStringBuffer` to bytes on an `OutputStream` using the specified character encoding.
`static void`	`write(StringBuilder data, Writer output)` Writes chars from a `AppendingStringBuffer` to a `Writer`.
`static void`	`write(String data, OutputStream output)` Writes chars from a `String` to bytes on an `OutputStream` using the default character encoding of the platform.
`static void`	`write(String data, OutputStream output, String encoding)` Writes chars from a `String` to bytes on an `OutputStream` using the specified character encoding.
`static void`	`write(String data, Writer output)` Writes chars from a `String` to a `Writer`.

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

- Constructor Detail
  - IOUtils
```
public IOUtils()
```
    Instances should NOT be constructed in standard programming.
- Method Detail
  - close
```
public static void close(Closeable closeable)
                  throws IOException
```
    Closes a closeable. Guards against null closables.
    
    Parameters:
    
    closeable - closeable to close
    
    Throws:
    
    IOException - when close fails
  - closeQuietly
```
public static void closeQuietly(Closeable closeable)
```
    Unconditionally close a Closeable.
    closeables can be input or output streams, reader, writers, and much more. Equivalent to Closeable.close(), except any exceptions will be ignored. This is typically used in finally blocks.
    
    Parameters:
    
    closeable - the Closeable to close, may be null or already closed
  - toByteArray
```
public static byte[] toByteArray(InputStream input)
                          throws IOException
```
    Get the contents of an InputStream as a byte[].
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    input - the InputStream to read from
    
    Returns:
    
    the requested byte array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toByteArray
```
public static byte[] toByteArray(Reader input)
                          throws IOException
```
    Get the contents of a Reader as a byte[] using the default character encoding of the platform.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    
    Parameters:
    
    input - the Reader to read from
    
    Returns:
    
    the requested byte array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toByteArray
```
public static byte[] toByteArray(Reader input,
                                 String encoding)
                          throws IOException
```
    Get the contents of a Reader as a byte[] using the specified character encoding.
    Character encoding names can be found at IANA.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    
    Parameters:
    
    input - the Reader to read from
    
    encoding - the encoding to use, null means platform default
    
    Returns:
    
    the requested byte array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - toCharArray
```
public static char[] toCharArray(InputStream is)
                          throws IOException
```
    Get the contents of an InputStream as a character array using the default character encoding of the platform.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    is - the InputStream to read from
    
    Returns:
    
    the requested character array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toCharArray
```
public static char[] toCharArray(InputStream is,
                                 String encoding)
                          throws IOException
```
    Get the contents of an InputStream as a character array using the specified character encoding.
    Character encoding names can be found at IANA.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    is - the InputStream to read from
    
    encoding - the encoding to use, null means platform default
    
    Returns:
    
    the requested character array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toCharArray
```
public static char[] toCharArray(Reader input)
                          throws IOException
```
    Get the contents of a Reader as a character array.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    
    Parameters:
    
    input - the Reader to read from
    
    Returns:
    
    the requested character array
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toString
```
public static String toString(InputStream input)
                       throws IOException
```
    Get the contents of an InputStream as a String using the default character encoding of the platform.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    input - the InputStream to read from
    
    Returns:
    
    the requested String
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toString
```
public static String toString(InputStream input,
                              String encoding)
                       throws IOException
```
    Get the contents of an InputStream as a String using the specified character encoding.
    Character encoding names can be found at IANA.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    input - the InputStream to read from
    
    encoding - the encoding to use, null means platform default
    
    Returns:
    
    the requested String
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - toString
```
public static String toString(Reader input)
                       throws IOException
```
    Get the contents of a Reader as a String.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    
    Parameters:
    
    input - the Reader to read from
    
    Returns:
    
    the requested String
    
    Throws:
    
    NullPointerException - if the input is null
    
    IOException - if an I/O error occurs
  - write
```
public static void write(byte[] data,
                         OutputStream output)
                  throws IOException
```
    Writes bytes from a byte[] to an OutputStream.
    
    Parameters:
    
    data - the byte array to write, do not modify during output, null ignored
    
    output - the OutputStream to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(byte[] data,
                         Writer output)
                  throws IOException
```
    Writes bytes from a byte[] to chars on a Writer using the default character encoding of the platform.
    This method uses String.String(byte[]).
    
    Parameters:
    
    data - the byte array to write, do not modify during output, null ignored
    
    output - the Writer to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(byte[] data,
                         Writer output,
                         String encoding)
                  throws IOException
```
    Writes bytes from a byte[] to chars on a Writer using the specified character encoding.
    Character encoding names can be found at IANA.
    This method uses String.String(byte[], String).
    
    Parameters:
    
    data - the byte array to write, do not modify during output, null ignored
    
    output - the Writer to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(char[] data,
                         Writer output)
                  throws IOException
```
    Writes chars from a char[] to a Writer using the default character encoding of the platform.
    
    Parameters:
    
    data - the char array to write, do not modify during output, null ignored
    
    output - the Writer to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(char[] data,
                         OutputStream output)
                  throws IOException
```
    Writes chars from a char[] to bytes on an OutputStream.
    This method uses String.String(char[]) and String.getBytes().
    
    Parameters:
    
    data - the char array to write, do not modify during output, null ignored
    
    output - the OutputStream to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(char[] data,
                         OutputStream output,
                         String encoding)
                  throws IOException
```
    Writes chars from a char[] to bytes on an OutputStream using the specified character encoding.
    Character encoding names can be found at IANA.
    This method uses String.String(char[]) and String.getBytes(String).
    
    Parameters:
    
    data - the char array to write, do not modify during output, null ignored
    
    output - the OutputStream to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(String data,
                         Writer output)
                  throws IOException
```
    Writes chars from a String to a Writer.
    
    Parameters:
    
    data - the String to write, null ignored
    
    output - the Writer to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(String data,
                         OutputStream output)
                  throws IOException
```
    Writes chars from a String to bytes on an OutputStream using the default character encoding of the platform.
    This method uses String.getBytes().
    
    Parameters:
    
    data - the String to write, null ignored
    
    output - the OutputStream to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(String data,
                         OutputStream output,
                         String encoding)
                  throws IOException
```
    Writes chars from a String to bytes on an OutputStream using the specified character encoding.
    Character encoding names can be found at IANA.
    This method uses String.getBytes(String).
    
    Parameters:
    
    data - the String to write, null ignored
    
    output - the OutputStream to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(StringBuilder data,
                         Writer output)
                  throws IOException
```
    Writes chars from a AppendingStringBuffer to a Writer.
    
    Parameters:
    
    data - the AppendingStringBuffer to write, null ignored
    
    output - the Writer to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(StringBuilder data,
                         OutputStream output)
                  throws IOException
```
    Writes chars from a AppendingStringBuffer to bytes on an OutputStream using the default character encoding of the platform.
    This method uses String.getBytes().
    
    Parameters:
    
    data - the AppendingStringBuffer to write, null ignored
    
    output - the OutputStream to write to
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - write
```
public static void write(StringBuilder data,
                         OutputStream output,
                         String encoding)
                  throws IOException
```
    Writes chars from a AppendingStringBuffer to bytes on an OutputStream using the specified character encoding.
    Character encoding names can be found at IANA.
    This method uses String.getBytes(String).
    
    Parameters:
    
    data - the AppendingStringBuffer to write, null ignored
    
    output - the OutputStream to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static int copy(InputStream input,
                       OutputStream output)
                throws IOException
```
    Copy bytes from an InputStream to an OutputStream.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    
    Parameters:
    
    input - the InputStream to read from
    
    output - the OutputStream to write to
    
    Returns:
    
    the number of bytes copied
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static void copy(InputStream input,
                        Writer output)
                 throws IOException
```
    Copy bytes from an InputStream to chars on a Writer using the default character encoding of the platform.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    This method uses InputStreamReader.
    
    Parameters:
    
    input - the InputStream to read from
    
    output - the Writer to write to
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static void copy(InputStream input,
                        Writer output,
                        String encoding)
                 throws IOException
```
    Copy bytes from an InputStream to chars on a Writer using the specified character encoding.
    This method buffers the input internally, so there is no need to use a BufferedInputStream.
    Character encoding names can be found at IANA.
    This method uses InputStreamReader.
    
    Parameters:
    
    input - the InputStream to read from
    
    output - the Writer to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static int copy(Reader input,
                       Writer output)
                throws IOException
```
    Copy chars from a Reader to a Writer.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    
    Parameters:
    
    input - the Reader to read from
    
    output - the Writer to write to
    
    Returns:
    
    the number of characters copied
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static void copy(Reader input,
                        OutputStream output)
                 throws IOException
```
    Copy chars from a Reader to bytes on an OutputStream using the default character encoding of the platform, and calling flush.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    Due to the implementation of OutputStreamWriter, this method performs a flush.
    This method uses OutputStreamWriter.
    
    Parameters:
    
    input - the Reader to read from
    
    output - the OutputStream to write to
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - copy
```
public static void copy(Reader input,
                        OutputStream output,
                        String encoding)
                 throws IOException
```
    Copy chars from a Reader to bytes on an OutputStream using the specified character encoding, and calling flush.
    This method buffers the input internally, so there is no need to use a BufferedReader.
    Character encoding names can be found at IANA.
    Due to the implementation of OutputStreamWriter, this method performs a flush.
    This method uses OutputStreamWriter.
    
    Parameters:
    
    input - the Reader to read from
    
    output - the OutputStream to write to
    
    encoding - the encoding to use, null means platform default
    
    Throws:
    
    NullPointerException - if the input or output is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1
  - contentEquals
```
public static boolean contentEquals(InputStream input1,
                                    InputStream input2)
                             throws IOException
```
    Compare the contents of two Streams to determine if they are equal or not.
    This method buffers the input internally using BufferedInputStream if they are not already buffered.
    
    Parameters:
    
    input1 - the first stream
    
    input2 - the second stream
    
    Returns:
    
    true if the content of the streams are equal or they both don't exist, false otherwise
    
    Throws:
    
    NullPointerException - if either input is null
    
    IOException - if an I/O error occurs
  - contentEquals
```
public static boolean contentEquals(Reader input1,
                                    Reader input2)
                             throws IOException
```
    Compare the contents of two Readers to determine if they are equal or not.
    This method buffers the input internally using BufferedReader if they are not already buffered.
    
    Parameters:
    
    input1 - the first reader
    
    input2 - the second reader
    
    Returns:
    
    true if the content of the readers are equal or they both don't exist, false otherwise
    
    Throws:
    
    NullPointerException - if either input is null
    
    IOException - if an I/O error occurs
    
    Since:
    
    1.1

Class IOUtils

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

IOUtils

Method Detail

close

closeQuietly

toByteArray

toByteArray

toByteArray

toCharArray

toCharArray

toCharArray

toString

toString

toString

write

write

write

write

write

write

write

write

write

write

write

write

copy

copy

copy

copy

copy

copy

contentEquals

contentEquals