Package org.apache.camel.util

Class IOHelper

java.lang.Object

org.apache.camel.util.IOHelper

public final class IOHelper
extends Object

IO helper class.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	IOHelper.EncodingFileReader	Encoding-aware file reader.
static class	IOHelper.EncodingFileWriter	Encoding-aware file writer.
static class	IOHelper.EncodingInputStream	Encoding-aware input stream.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_BUFFER_SIZE
static Supplier<Charset>	defaultCharset
static final long	INITIAL_OFFSET

Method Summary

Modifier and Type	Method	Description
static void	appendText(String text, File file)	Appends the text to the file.
static BufferedInputStream	buffered(InputStream in)	Wraps the passed in into a BufferedInputStream object and returns that.
static BufferedOutputStream	buffered(OutputStream out)	Wraps the passed out into a BufferedOutputStream object and returns that.
static BufferedReader	buffered(Reader reader)	Wraps the passed reader into a BufferedReader object and returns that.
static BufferedWriter	buffered(Writer writer)	Wraps the passed writer into a BufferedWriter object and returns that.
static void	close(Closeable closeable)	Closes the given resource if it is available.
static void	close(Closeable... closeables)	Closes the given resources if they are available.
static void	close(Closeable closeable, String name)	Closes the given resource if it is available.
static void	close(Closeable closeable, String name, org.slf4j.Logger log)	Closes the given resource if it is available, logging any closing exceptions to the given log.
static void	close(Writer writer, FileOutputStream os, String name, org.slf4j.Logger log, boolean force)	Closes the given writer, logging any closing exceptions to the given log.
static void	close(FileChannel channel, String name, org.slf4j.Logger log, boolean force)	Closes the given channel if it is available, logging any closing exceptions to the given log.
static void	closeIterator(Object it)
static void	closeWithException(Closeable closeable)	Closes the given resource if it is available and don't catch the exception
static int	copy(InputStream input, OutputStream output)
static int	copy(InputStream input, OutputStream output, int bufferSize)
static int	copy(InputStream input, OutputStream output, int bufferSize, boolean flushOnEachWrite)
static int	copy(InputStream input, OutputStream output, int bufferSize, boolean flushOnEachWrite, long maxSize)
static int	copy(Reader input, Writer output, int bufferSize)
static void	copyAndCloseInput(InputStream input, OutputStream output)
static void	copyAndCloseInput(InputStream input, OutputStream output, int bufferSize)
static void	force(FileOutputStream os, String name, org.slf4j.Logger log)	Forces any updates to a FileOutputStream be written to the storage device that contains it.
static void	force(FileChannel channel, String name, org.slf4j.Logger log)	Forces any updates to this channel's file to be written to the storage device that contains it.
static String	getCharsetNameFromContentType(String contentType)	Get the charset name from the content type string
static String	loadText(InputStream in)	Loads the entire stream into memory as a String and returns it.
static String	loadTextLine(InputStream in, int lineNumber)	Loads the entire stream into memory as a String and returns the given line number.
static String	lookupEnvironmentVariable(String key)	Lookup the OS environment variable in a safe manner by using upper case keys and underscore instead of dash.
static String	normalizeCharset(String charset)	This method will take off the quotes and double quotes of the charset
static String	stripLineComments(Path path, String commentPrefix, boolean stripBlankLines)	Reads the file under the given path, strips lines starting with commentPrefix and optionally also strips blank lines (the ones for which String.isBlank() returns true.
static InputStream	toInputStream(File file, String charset)	Converts the given File with the given charset to InputStream with the JVM default charset
static BufferedReader	toReader(File file, String charset)
static BufferedReader	toReader(File file, Charset charset)
static String	toString(BufferedReader reader)
static String	toString(BufferedReader reader, long offset)
static String	toString(Reader reader)
static String	toString(Reader reader, long offset)
static BufferedWriter	toWriter(FileOutputStream os, String charset)
static BufferedWriter	toWriter(FileOutputStream os, Charset charset)
static void	transfer(ReadableByteChannel input, WritableByteChannel output)
static void	validateCharset(String charset)
static void	writeText(String text, File file)	Writes the text to the file.
static void	writeText(String text, OutputStream os)	Writes the text to the stream.

Methods inherited from class java.lang.Object

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

Field Details

defaultCharset

public static Supplier<Charset> defaultCharset

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

See Also:

• Constant Field Values

INITIAL_OFFSET

public static final long INITIAL_OFFSET

See Also:

• Constant Field Values

Method Details

buffered

public static BufferedInputStream buffered(InputStream in)

Wraps the passed in into a BufferedInputStream object and returns that. If the passed in is already an instance of BufferedInputStream returns the same passed in reference as is (avoiding double wrapping).

Parameters:

in - the wrapee to be used for the buffering support

Returns:

the passed in decorated through a BufferedInputStream object as wrapper

buffered

public static BufferedOutputStream buffered(OutputStream out)

Wraps the passed out into a BufferedOutputStream object and returns that. If the passed out is already an instance of BufferedOutputStream returns the same passed out reference as is (avoiding double wrapping).

Parameters:

out - the wrapee to be used for the buffering support

Returns:

the passed out decorated through a BufferedOutputStream object as wrapper

buffered

public static BufferedReader buffered(Reader reader)

Wraps the passed reader into a BufferedReader object and returns that. If the passed reader is already an instance of BufferedReader returns the same passed reader reference as is (avoiding double wrapping).

Parameters:

reader - the wrapee to be used for the buffering support

Returns:

the passed reader decorated through a BufferedReader object as wrapper

buffered

public static BufferedWriter buffered(Writer writer)

Wraps the passed writer into a BufferedWriter object and returns that. If the passed writer is already an instance of BufferedWriter returns the same passed writer reference as is (avoiding double wrapping).

Parameters:

writer - the writer to be used for the buffering support

Returns:

the passed writer decorated through a BufferedWriter object as wrapper

toString

public static String toString(Reader reader)
                       throws IOException

Throws:

IOException

toString

public static String toString(Reader reader,
 long offset)
                       throws IOException

Throws:

IOException

toString

public static String toString(BufferedReader reader)
                       throws IOException

Throws:

IOException

toString

public static String toString(BufferedReader reader,
 long offset)
                       throws IOException

Throws:

IOException

copy

public static int copy(InputStream input,
 OutputStream output)
                throws IOException

Throws:

IOException

copy

public static int copy(InputStream input,
 OutputStream output,
 int bufferSize)
                throws IOException

Throws:

IOException

copy

public static int copy(InputStream input,
 OutputStream output,
 int bufferSize,
 boolean flushOnEachWrite)
                throws IOException

Throws:

IOException

copy

public static int copy(InputStream input,
 OutputStream output,
 int bufferSize,
 boolean flushOnEachWrite,
 long maxSize)
                throws IOException

Throws:

IOException

copyAndCloseInput

public static void copyAndCloseInput(InputStream input,
 OutputStream output)
                              throws IOException

Throws:

IOException

copyAndCloseInput

public static void copyAndCloseInput(InputStream input,
 OutputStream output,
 int bufferSize)
                              throws IOException

Throws:

IOException

copy

public static int copy(Reader input,
 Writer output,
 int bufferSize)
                throws IOException

Throws:

IOException

transfer

public static void transfer(ReadableByteChannel input,
 WritableByteChannel output)
                     throws IOException

Throws:

IOException

force

public static void force(FileChannel channel,
 String name,
 org.slf4j.Logger log)

Forces any updates to this channel's file to be written to the storage device that contains it.

Parameters:

channel - the file channel

name - the name of the resource

log - the log to use when reporting warnings, will use this class's own Logger if log == null

force

public static void force(FileOutputStream os,
 String name,
 org.slf4j.Logger log)

Forces any updates to a FileOutputStream be written to the storage device that contains it.

Parameters:

os - the file output stream

name - the name of the resource

log - the log to use when reporting warnings, will use this class's own Logger if log == null

close

public static void close(Writer writer,
 FileOutputStream os,
 String name,
 org.slf4j.Logger log,
 boolean force)

Closes the given writer, logging any closing exceptions to the given log. An associated FileOutputStream can optionally be forced to disk.

Parameters:

writer - the writer to close

os - an underlying FileOutputStream that will to be forced to disk according to the force parameter

name - the name of the resource

log - the log to use when reporting warnings, will use this class's own Logger if log == null

force - forces the FileOutputStream to disk

close

public static void close(Closeable closeable,
 String name,
 org.slf4j.Logger log)

Closes the given resource if it is available, logging any closing exceptions to the given log.

Parameters:

closeable - the object to close

name - the name of the resource

log - the log to use when reporting closure warnings, will use this class's own Logger if log == null

closeWithException

public static void closeWithException(Closeable closeable)
                               throws IOException

Closes the given resource if it is available and don't catch the exception

Parameters:

closeable - the object to close

Throws:

IOException

close

public static void close(FileChannel channel,
 String name,
 org.slf4j.Logger log,
 boolean force)

Closes the given channel if it is available, logging any closing exceptions to the given log. The file's channel can optionally be forced to disk.

Parameters:

channel - the file channel

name - the name of the resource

log - the log to use when reporting warnings, will use this class's own Logger if log == null

force - forces the file channel to disk

close

public static void close(Closeable closeable,
 String name)

Closes the given resource if it is available.

Parameters:

closeable - the object to close

name - the name of the resource

close

public static void close(Closeable closeable)

Closes the given resource if it is available.

Parameters:

closeable - the object to close

close

public static void close(Closeable... closeables)

Closes the given resources if they are available.

Parameters:

closeables - the objects to close

closeIterator

public static void closeIterator(Object it)
                          throws IOException

Throws:

IOException

validateCharset

public static void validateCharset(String charset)
                            throws UnsupportedCharsetException

Throws:

UnsupportedCharsetException

loadText

public static String loadText(InputStream in)
                       throws IOException

Loads the entire stream into memory as a String and returns it.

Notice: This implementation appends a \n as line terminator at the of the text.

Warning, don't use for crazy big streams :)

Throws:

IOException

loadTextLine

public static String loadTextLine(InputStream in,
 int lineNumber)
                           throws IOException

Loads the entire stream into memory as a String and returns the given line number.

Warning, don't use for crazy big streams :)

Throws:

IOException

appendText

public static void appendText(String text,
 File file)
                       throws IOException

Appends the text to the file.

Throws:

IOException

writeText

public static void writeText(String text,
 File file)
                      throws IOException

Writes the text to the file.

Throws:

IOException

writeText

public static void writeText(String text,
 OutputStream os)
                      throws IOException

Writes the text to the stream.

Throws:

IOException

getCharsetNameFromContentType

public static String getCharsetNameFromContentType(String contentType)

Get the charset name from the content type string

Parameters:

contentType - the content type

Returns:

the charset name, or UTF-8 if no found

normalizeCharset

public static String normalizeCharset(String charset)

This method will take off the quotes and double quotes of the charset

lookupEnvironmentVariable

public static String lookupEnvironmentVariable(String key)

Lookup the OS environment variable in a safe manner by using upper case keys and underscore instead of dash.

toInputStream

public static InputStream toInputStream(File file,
 String charset)
                                 throws IOException

Converts the given File with the given charset to InputStream with the JVM default charset

Parameters:

file - the file to be converted

charset - the charset the file is read with

Returns:

the input stream with the JVM default charset

Throws:

IOException

toReader

public static BufferedReader toReader(File file,
 String charset)
                               throws IOException

Throws:

IOException

toReader

public static BufferedReader toReader(File file,
 Charset charset)
                               throws IOException

Throws:

IOException

toWriter

public static BufferedWriter toWriter(FileOutputStream os,
 String charset)
                               throws IOException

Throws:

IOException

toWriter

public static BufferedWriter toWriter(FileOutputStream os,
 Charset charset)

stripLineComments

public static String stripLineComments(Path path,
 String commentPrefix,
 boolean stripBlankLines)

Reads the file under the given path, strips lines starting with commentPrefix and optionally also strips blank lines (the ones for which String.isBlank() returns true. Normalizes EOL characters to '\n'.

Parameters:

path - the path of the file to read

commentPrefix - the leading character sequence of comment lines.

stripBlankLines - if true true the lines matching String.isBlank() will not appear in the result

Returns:

the filtered content of the file