com.github.robtimus.filesystems

Class FileSystemProviderSupport

java.lang.Object

com.github.robtimus.filesystems.FileSystemProviderSupport

public final class FileSystemProviderSupport
extends Object

A utility class that can assist in implementing FileSystemProviders.

Author:

Rob Spoor

Method Summary

Modifier and Type	Method and Description
static SeekableByteChannel	createSeekableByteChannel(InputStream in, long size) Creates a SeekableByteChannel wrapped around an InputStream.
static SeekableByteChannel	createSeekableByteChannel(InputStream in, long size, long initialPosition) Creates a SeekableByteChannel wrapped around an InputStream.
static SeekableByteChannel	createSeekableByteChannel(OutputStream out) Creates a SeekableByteChannel wrapped around an OutputStream.
static SeekableByteChannel	createSeekableByteChannel(OutputStream out, long initialPosition) Creates a SeekableByteChannel wrapped around an OutputStream.
static boolean	getBooleanValue(Map<String,?> env, String property) Retrieves a required boolean property from a map.
static boolean	getBooleanValue(Map<String,?> env, String property, boolean defaultValue) Retrieves an optional boolean property from a map.
static byte	getByteValue(Map<String,?> env, String property) Retrieves a required byte property from a map.
static byte	getByteValue(Map<String,?> env, String property, byte defaultValue) Retrieves an optional byte property from a map.
static double	getDoubleValue(Map<String,?> env, String property) Retrieves a required double property from a map.
static double	getDoubleValue(Map<String,?> env, String property, double defaultValue) Retrieves an optional double property from a map.
static float	getFloatValue(Map<String,?> env, String property) Retrieves a required float property from a map.
static float	getFloatValue(Map<String,?> env, String property, float defaultValue) Retrieves an optional float property from a map.
static int	getIntValue(Map<String,?> env, String property) Retrieves a required int property from a map.
static int	getIntValue(Map<String,?> env, String property, int defaultValue) Retrieves an optional int property from a map.
static long	getLongValue(Map<String,?> env, String property) Retrieves a required long property from a map.
static long	getLongValue(Map<String,?> env, String property, long defaultValue) Retrieves an optional long property from a map.
static short	getShortValue(Map<String,?> env, String property) Retrieves a required short property from a map.
static short	getShortValue(Map<String,?> env, String property, short defaultValue) Retrieves an optional short property from a map.
static <T> T	getValue(Map<String,?> env, String property, Class<T> cls) Retrieves a required property from a map.
static <T> T	getValue(Map<String,?> env, String property, Class<T> cls, T defaultValue) Retrieves an optional property from a map.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

createSeekableByteChannel

public static SeekableByteChannel createSeekableByteChannel(InputStream in,
                                                            long size)

Creates a SeekableByteChannel wrapped around an InputStream. This SeekableByteChannel, with an initial position of 0 does not support seeking a specific position, truncating or writing.

Parameters:

in - The InputStream to wrap.

size - The size of the source of the InputStream.

Returns:

The created SeekableByteChannel.

Throws:

NullPointerException - If the given InputStream is null.

IllegalArgumentException - If the given size of initial position is negative.

createSeekableByteChannel

public static SeekableByteChannel createSeekableByteChannel(InputStream in,
                                                            long size,
                                                            long initialPosition)

Creates a SeekableByteChannel wrapped around an InputStream. This SeekableByteChannel does not support seeking a specific position, truncating or writing.

Parameters:

in - The InputStream to wrap.

size - The size of the source of the InputStream.

initialPosition - The initial position of the returned SeekableByteChannel.

Returns:

The created SeekableByteChannel.

Throws:

NullPointerException - If the given InputStream is null.

IllegalArgumentException - If the given size of initial position is negative.

createSeekableByteChannel

public static SeekableByteChannel createSeekableByteChannel(OutputStream out)

Creates a SeekableByteChannel wrapped around an OutputStream. This SeekableByteChannel, with an initial position of 0, does not support seeking a specific position, truncating or reading.

Parameters:

out - The OutputStream to wrap.

Returns:

The created SeekableByteChannel.

Throws:

NullPointerException - If the given OutputStream is null.

createSeekableByteChannel

public static SeekableByteChannel createSeekableByteChannel(OutputStream out,
                                                            long initialPosition)

Creates a SeekableByteChannel wrapped around an OutputStream. This SeekableByteChannel does not support seeking a specific position, truncating or reading.

Parameters:

out - The OutputStream to wrap.

initialPosition - The initial position of the returned SeekableByteChannel.

Returns:

The created SeekableByteChannel.

Throws:

NullPointerException - If the given OutputStream is null.

IllegalArgumentException - If the given initial position is negative.

getBooleanValue

public static boolean getBooleanValue(Map<String,?> env,
                                      String property)

Retrieves a required boolean property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Boolean and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getBooleanValue

public static boolean getBooleanValue(Map<String,?> env,
                                      String property,
                                      boolean defaultValue)

Retrieves an optional boolean property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Boolean and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getByteValue

public static byte getByteValue(Map<String,?> env,
                                String property)

Retrieves a required byte property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Byte and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getByteValue

public static byte getByteValue(Map<String,?> env,
                                String property,
                                byte defaultValue)

Retrieves an optional byte property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Byte and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getShortValue

public static short getShortValue(Map<String,?> env,
                                  String property)

Retrieves a required short property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Short and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getShortValue

public static short getShortValue(Map<String,?> env,
                                  String property,
                                  short defaultValue)

Retrieves an optional short property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Short and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getIntValue

public static int getIntValue(Map<String,?> env,
                              String property)

Retrieves a required int property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Integer and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getIntValue

public static int getIntValue(Map<String,?> env,
                              String property,
                              int defaultValue)

Retrieves an optional int property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Integer and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getLongValue

public static long getLongValue(Map<String,?> env,
                                String property)

Retrieves a required long property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Long and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getLongValue

public static long getLongValue(Map<String,?> env,
                                String property,
                                long defaultValue)

Retrieves an optional long property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Long and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getFloatValue

public static float getFloatValue(Map<String,?> env,
                                  String property)

Retrieves a required float property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Float and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getFloatValue

public static float getFloatValue(Map<String,?> env,
                                  String property,
                                  float defaultValue)

Retrieves an optional float property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Float and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getDoubleValue

public static double getDoubleValue(Map<String,?> env,
                                    String property)

Retrieves a required double property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Double and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getDoubleValue

public static double getDoubleValue(Map<String,?> env,
                                    String property,
                                    double defaultValue)

Retrieves an optional double property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map). It supports values of type Double and String.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.

getValue

public static <T> T getValue(Map<String,?> env,
                             String property,
                             Class<T> cls)

Retrieves a required property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map).

Type Parameters:

T - The property type.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

cls - The class the property should be an instance of.

Returns:

The value for the given property.

Throws:

IllegalArgumentException - If the property is not present in the given map, or if its value has an incompatible type.

getValue

public static <T> T getValue(Map<String,?> env,
                             String property,
                             Class<T> cls,
                             T defaultValue)

Retrieves an optional property from a map. This method can be used to retrieve properties in implementations of FileSystemProvider.newFileSystem(URI, Map) and FileSystemProvider.newFileSystem(Path, Map).

Type Parameters:

T - The property type.

Parameters:

env - The map to retrieve the property from.

property - The name of the property.

cls - The class the property should be an instance of.

defaultValue - The value that should be used if the property is not in the given map.

Returns:

The value for the given property, or the given default value if the property is not in the given map.

Throws:

IllegalArgumentException - If the property's value has an incompatible type.