Package com.helger.base.io.stream

Class StreamHelper

java.lang.Object

com.helger.base.io.stream.StreamHelper

@Immutable
public class StreamHelper
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	StreamHelper.CopyByteStreamBuilder	A simple builder to copy an InputStream (StreamHelper.CopyByteStreamBuilder.from(InputStream)) to an OutputStream (StreamHelper.CopyByteStreamBuilder.to(OutputStream)) with certain parameters.
static class	StreamHelper.CopyCharStreamBuilder	A simple builder to copy a Reader (StreamHelper.CopyCharStreamBuilder.from(Reader)) to an Writer (StreamHelper.CopyCharStreamBuilder.to(Writer)) with certain parameters.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_BUFSIZE	buffer size for copy operations
static final int	END_OF_STRING_MARKER

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	StreamHelper()

Method Summary

Modifier and Type	Method	Description
static InputStream	checkForInvalidFilterInputStream(InputStream aIS)
static ESuccess	close(AutoCloseable aCloseable)	Close the passed stream by encapsulating the declared IOException.
static ESuccess	closeWithoutFlush(AutoCloseable aCloseable)	Close the passed object, without trying to call flush on it.
static StreamHelper.CopyByteStreamBuilder	copyByteStream()
static StreamHelper.CopyCharStreamBuilder	copyCharStream()
static ESuccess	copyInputStreamToOutputStream(InputStream aIS, OutputStream aOS)	Pass the content of the given input stream to the given output stream.
static ESuccess	copyInputStreamToOutputStreamAndCloseOS(InputStream aIS, OutputStream aOS)	Pass the content of the given input stream to the given output stream.
static ESuccess	copyReaderToWriter(Reader aReader, Writer aWriter)	Pass the content of the given reader to the given writer.
static ESuccess	copyReaderToWriterAndCloseWriter(Reader aReader, Writer aWriter)	Pass the content of the given reader to the given writer.
static byte[]	createDefaultCopyBufferBytes()
static char[]	createDefaultCopyBufferChars()
static NonBlockingStringReader	createReader(char[] aChars)
static InputStreamReader	createReader(InputStream aIS, Charset aCharset)
static NonBlockingStringReader	createReader(String sText)
static OutputStreamWriter	createWriter(OutputStream aOS, Charset aCharset)
static ESuccess	flush(Flushable aFlushable)	Flush the passed object encapsulating the declared IOException.
static byte[]	getAllBytes(IHasInputStream aISP)	Read all bytes from the passed input stream into a byte array.
static byte[]	getAllBytes(InputStream aIS)	Read all bytes from the passed input stream into a byte array.
static String	getAllBytesAsString(IHasInputStream aISP, Charset aCharset)	Read all bytes from the passed input stream into a string.
static String	getAllBytesAsString(InputStream aIS, Charset aCharset)	Read all bytes from the passed input stream into a string.
static char[]	getAllCharacters(Reader aReader)	Read all characters from the passed reader into a char array.
static String	getAllCharactersAsString(Reader aReader)	Read all characters from the passed reader into a String.
static int	getAvailable(InputStream aIS)	Get the number of available bytes in the passed input stream.
static InputStream	getBuffered(InputStream aIS)
static OutputStream	getBuffered(OutputStream aOS)
static Reader	getBuffered(Reader aReader)
static Writer	getBuffered(Writer aWriter)
static NonBlockingByteArrayOutputStream	getCopy(InputStream aIS)	Get a byte buffer with all the available content of the passed input stream.
static NonBlockingStringWriter	getCopy(Reader aReader)
static NonBlockingByteArrayOutputStream	getCopyWithLimit(InputStream aIS, long nLimit)	Get a byte buffer with all the available content of the passed input stream.
static NonBlockingStringWriter	getCopyWithLimit(Reader aReader, long nLimit)
protected static Exception	internalGetPropagatableException(Exception ex)
static boolean	isBuffered(InputStream aIS)
static boolean	isBuffered(OutputStream aOS)
static boolean	isBuffered(Reader aReader)
static boolean	isBuffered(Writer aWriter)
static boolean	isKnownEOFException(Class<?> aClass)	Check if the passed class is a known EOF exception class.
static boolean	isKnownEOFException(Throwable t)	Check if the passed exception is a known EOF exception.
static int	readFully(InputStream aIS, byte[] aBuffer)	Read the whole buffer from the input stream.
static int	readFully(InputStream aIS, byte[] aBuffer, int nOfs, int nLen)	Read the whole buffer from the input stream.
static String	readSafeUTF(DataInput aDI)	Because DataOutputStream.writeUTF(String) has a limit of 64KB this methods provides a similar solution for reading like DataInputStream.readUTF() but what was written in writeSafeUTF(DataOutput, String).
static void	readUntilEOF(InputStream aIS, byte[] aBuffer, ObjIntConsumer<? super byte[]> aConsumer)
static void	readUntilEOF(InputStream aIS, ObjIntConsumer<? super byte[]> aConsumer)
static void	readUntilEOF(Reader aReader, char[] aBuffer, ObjIntConsumer<? super char[]> aConsumer)
static void	readUntilEOF(Reader aReader, ObjIntConsumer<? super char[]> aConsumer)
static void	skipFully(InputStream aIS, long nBytesToSkip)	Fully skip the passed amounts in the input stream.
static void	writeSafeUTF(DataOutput aDO, String sStr)	Because DataOutputStream.writeUTF(String) has a limit of 64KB this methods provides a similar solution but simply writing the bytes.
static ESuccess	writeStream(OutputStream aOS, byte[] aBuf)	Write bytes to an OutputStream.
static ESuccess	writeStream(OutputStream aOS, byte[] aBuf, int nOfs, int nLen)	Write bytes to an OutputStream.
static ESuccess	writeStream(OutputStream aOS, String sContent, Charset aCharset)	Write bytes to an OutputStream.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_BUFSIZE

public static final int DEFAULT_BUFSIZE

buffer size for copy operations

See Also:

• Constant Field Values

END_OF_STRING_MARKER

public static final int END_OF_STRING_MARKER

See Also:

• Constant Field Values

Constructor Details

StreamHelper

protected StreamHelper()

Method Details

createDefaultCopyBufferBytes

@Nonnull
@ReturnsMutableCopy
public static byte[] createDefaultCopyBufferBytes()

Returns:

A newly created copy buffer using DEFAULT_BUFSIZE. Never null.

Since:

9.3.6

createDefaultCopyBufferChars

@Nonnull
@ReturnsMutableCopy
public static char[] createDefaultCopyBufferChars()

Returns:

A newly created copy buffer using DEFAULT_BUFSIZE. Never null.

Since:

9.3.6

createReader

@Nonnull
public static NonBlockingStringReader createReader(@Nonnull
 String sText)

createReader

@Nonnull
public static NonBlockingStringReader createReader(@Nonnull
 char[] aChars)

createReader

@Nullable
public static InputStreamReader createReader(@Nullable
 InputStream aIS,
 @Nonnull
 Charset aCharset)

createWriter

@Nullable
public static OutputStreamWriter createWriter(@Nullable
 OutputStream aOS,
 @Nonnull
 Charset aCharset)

isKnownEOFException

public static boolean isKnownEOFException(@Nullable
 Throwable t)

Check if the passed exception is a known EOF exception.

Parameters:

t - The throwable/exception to be checked. May be null.

Returns:

true if it is a user-created EOF exception

isKnownEOFException

public static boolean isKnownEOFException(@Nullable
 Class<?> aClass)

Check if the passed class is a known EOF exception class.

Parameters:

aClass - The class to be checked. May be null.

Returns:

true if it is a known EOF exception class.

internalGetPropagatableException

@Nullable
protected static Exception internalGetPropagatableException(@Nonnull
 Exception ex)

closeWithoutFlush

@Nonnull
public static ESuccess closeWithoutFlush(@Nullable @WillClose
 AutoCloseable aCloseable)

Close the passed object, without trying to call flush on it.

Parameters:

aCloseable - The object to be closed. May be null.

Returns:

ESuccess.SUCCESS if the object was successfully closed.

close

@Nonnull
public static ESuccess close(@Nullable @WillClose
 AutoCloseable aCloseable)

Close the passed stream by encapsulating the declared IOException. If the passed object also implements the Flushable interface, it is tried to be flushed before it is closed.

Parameters:

aCloseable - The object to be closed. May be null.

Returns:

ESuccess if the object was successfully closed.

flush

@Nonnull
public static ESuccess flush(@Nullable
 Flushable aFlushable)

Flush the passed object encapsulating the declared IOException.

Parameters:

aFlushable - The flushable to be flushed. May be null.

Returns:

ESuccess.SUCCESS if the object was successfully flushed.

isBuffered

public static boolean isBuffered(@Nullable
 InputStream aIS)

getBuffered

@Nullable
public static InputStream getBuffered(@Nullable
 InputStream aIS)

isBuffered

public static boolean isBuffered(@Nullable
 OutputStream aOS)

getBuffered

@Nullable
public static OutputStream getBuffered(@Nullable
 OutputStream aOS)

isBuffered

public static boolean isBuffered(@Nullable
 Reader aReader)

getBuffered

@Nullable
public static Reader getBuffered(@Nullable
 Reader aReader)

isBuffered

public static boolean isBuffered(@Nullable
 Writer aWriter)

getBuffered

@Nullable
public static Writer getBuffered(@Nullable
 Writer aWriter)

copyInputStreamToOutputStream

@Nonnull
public static ESuccess copyInputStreamToOutputStream(@WillClose @Nullable
 InputStream aIS,
 @WillNotClose @Nullable
 OutputStream aOS)

Pass the content of the given input stream to the given output stream. The input stream is automatically closed, whereas the output stream stays open!

Parameters:

aIS - The input stream to read from. May be null. Automatically closed!

aOS - The output stream to write to. May be null. Not automatically closed!

Returns:

ESuccess.SUCCESS if copying took place, ESuccess.FAILURE otherwise

copyInputStreamToOutputStreamAndCloseOS

@Nonnull
public static ESuccess copyInputStreamToOutputStreamAndCloseOS(@WillClose @Nullable
 InputStream aIS,
 @WillClose @Nullable
 OutputStream aOS)

Pass the content of the given input stream to the given output stream. Both the input stream and the output stream are automatically closed.

Parameters:

aIS - The input stream to read from. May be null. Automatically closed!

aOS - The output stream to write to. May be null. Automatically closed!

Returns:

ESuccess.SUCCESS if copying took place, ESuccess.FAILURE otherwise

copyByteStream

@Nonnull
public static StreamHelper.CopyByteStreamBuilder copyByteStream()

Returns:

A new StreamHelper.CopyByteStreamBuilder. Never null.

getAvailable

public static int getAvailable(@Nullable
 InputStream aIS)

Get the number of available bytes in the passed input stream.

Parameters:

aIS - The input stream to use. May be null.

Returns:

0 in case of an error or if the parameter was null.

getCopy

@Nullable
public static NonBlockingByteArrayOutputStream getCopy(@Nonnull @WillClose
 InputStream aIS)

Get a byte buffer with all the available content of the passed input stream.

Parameters:

aIS - The source input stream. May not be null.

Returns:

A new NonBlockingByteArrayOutputStream with all available content inside. The OutputStream must be closed by the caller since v10. Since v9.3.6 this method returns null if copying fails.

getCopyWithLimit

@Nullable
public static NonBlockingByteArrayOutputStream getCopyWithLimit(@Nonnull @WillClose
 InputStream aIS,
 @Nonnegative
 long nLimit)

Get a byte buffer with all the available content of the passed input stream.

Parameters:

aIS - The source input stream. May not be null.

nLimit - The maximum number of bytes to be copied to the output stream. Must be ≥ 0.

Returns:

A new NonBlockingByteArrayOutputStream with all available content inside. The OutputStream must be closed by the caller since v10. Since v9.3.6 this method returns null if copying fails.

getAllBytes

@Nullable
public static byte[] getAllBytes(@Nullable
 IHasInputStream aISP)

Read all bytes from the passed input stream into a byte array.

Parameters:

aISP - The input stream provider to read from. May be null .

Returns:

The byte array or null if the parameter or the resolved input stream is null.

getAllBytes

@Nullable
public static byte[] getAllBytes(@Nullable @WillClose
 InputStream aIS)

Read all bytes from the passed input stream into a byte array.

Parameters:

aIS - The input stream to read from. May be null.

Returns:

The byte array or null if the input stream is null.

getAllBytesAsString

@Nullable
public static String getAllBytesAsString(@Nullable
 IHasInputStream aISP,
 @Nonnull @Nonempty
 Charset aCharset)

Read all bytes from the passed input stream into a string.

Parameters:

aISP - The input stream provider to read from. May be null .

aCharset - The charset to use. May not be null .

Returns:

The String or null if the parameter or the resolved input stream is null.

getAllBytesAsString

@Nullable
public static String getAllBytesAsString(@Nullable @WillClose
 InputStream aIS,
 @Nonnull @Nonempty
 Charset aCharset)

Read all bytes from the passed input stream into a string.

Parameters:

aIS - The input stream to read from. May be null.

aCharset - The charset to use. May not be null .

Returns:

The String or null if the input stream is null.

copyReaderToWriter

@Nonnull
public static ESuccess copyReaderToWriter(@WillClose @Nullable
 Reader aReader,
 @WillNotClose @Nullable
 Writer aWriter)

Pass the content of the given reader to the given writer. The reader is automatically closed, whereas the writer stays open!

Parameters:

aReader - The reader to read from. May be null. Automatically closed!

aWriter - The writer to write to. May be null. Not automatically closed!

Returns:

ESuccess.SUCCESS if copying took place, ESuccess.FAILURE otherwise

copyReaderToWriterAndCloseWriter

@Nonnull
public static ESuccess copyReaderToWriterAndCloseWriter(@Nullable @WillClose
 Reader aReader,
 @Nullable @WillClose
 Writer aWriter)

Pass the content of the given reader to the given writer. The reader and the writer are automatically closed!

Parameters:

aReader - The reader to read from. May be null. Automatically closed!

aWriter - The writer to write to. May be null. Automatically closed!

Returns:

ESuccess.SUCCESS if copying took place, ESuccess.FAILURE otherwise

copyCharStream

@Nonnull
public static StreamHelper.CopyCharStreamBuilder copyCharStream()

Returns:

A new StreamHelper.CopyCharStreamBuilder. Never null.

getCopy

@Nullable
public static NonBlockingStringWriter getCopy(@Nonnull @WillClose
 Reader aReader)

getCopyWithLimit

@Nullable
public static NonBlockingStringWriter getCopyWithLimit(@Nonnull @WillClose
 Reader aReader,
 @Nonnegative
 long nLimit)

getAllCharacters

@Nullable
public static char[] getAllCharacters(@Nullable @WillClose
 Reader aReader)

Read all characters from the passed reader into a char array.

Parameters:

aReader - The reader to read from. May be null.

Returns:

The character array or null if the reader is null.

getAllCharactersAsString

@Nullable
public static String getAllCharactersAsString(@Nullable @WillClose
 Reader aReader)

Read all characters from the passed reader into a String.

Parameters:

aReader - The reader to read from. May be null.

Returns:

The character array or null if the reader is null.

writeStream

@Nonnull
public static ESuccess writeStream(@WillClose @Nonnull
 OutputStream aOS,
 @Nonnull
 byte[] aBuf,
 @Nonnegative
 int nOfs,
 @Nonnegative
 int nLen)

Write bytes to an OutputStream.

Parameters:

aOS - The output stream to write to. May not be null. Is closed independent of error or success.

aBuf - The byte array from which is to be written. May not be null.

nOfs - The 0-based index to the first byte in the array to be written. May not be < 0.

nLen - The non-negative amount of bytes to be written. May not be < 0.

Returns:

ESuccess

writeStream

@Nonnull
public static ESuccess writeStream(@WillClose @Nonnull
 OutputStream aOS,
 @Nonnull
 byte[] aBuf)

Write bytes to an OutputStream.

Parameters:

aOS - The output stream to write to. May not be null. Is closed independent of error or success.

aBuf - The byte array to be written. May not be null.

Returns:

ESuccess

writeStream

@Nonnull
public static ESuccess writeStream(@WillClose @Nonnull
 OutputStream aOS,
 @Nonnull
 String sContent,
 @Nonnull
 Charset aCharset)

Write bytes to an OutputStream.

Parameters:

aOS - The output stream to write to. May not be null. Is closed independent of error or success.

sContent - The string to be written. May not be null.

aCharset - The charset to be used, to convert the String to a byte array.

Returns:

ESuccess

skipFully

public static void skipFully(@Nonnull
 InputStream aIS,
 @Nonnegative
 long nBytesToSkip)
                      throws IOException

Fully skip the passed amounts in the input stream. Only forward skipping is possible!

Parameters:

aIS - The input stream to skip in.

nBytesToSkip - The number of bytes to skip. Must be ≥ 0.

Throws:

IOException - In case something goes wrong internally

readFully

@Nonnegative
public static int readFully(@Nonnull
 InputStream aIS,
 @Nonnull
 byte[] aBuffer)
                     throws IOException

Read the whole buffer from the input stream.

Parameters:

aIS - The input stream to read from. May not be null.

aBuffer - The buffer to write to. May not be null. Must be ≥ than the content to be read.

Returns:

The number of read bytes

Throws:

IOException - In case reading fails

readFully

@Nonnegative
public static int readFully(@Nonnull @WillNotClose
 InputStream aIS,
 @Nonnull
 byte[] aBuffer,
 @Nonnegative
 int nOfs,
 @Nonnegative
 int nLen)
                     throws IOException

Read the whole buffer from the input stream.

Parameters:

aIS - The input stream to read from. May not be null.

aBuffer - The buffer to write to. May not be null. Must be ≥ than the content to be read.

nOfs - The offset into the destination buffer to use. May not be < 0.

nLen - The number of bytes to read into the destination buffer to use. May not be < 0.

Returns:

The number of read bytes

Throws:

IOException - In case reading fails

readUntilEOF

public static void readUntilEOF(@Nonnull @WillClose
 InputStream aIS,
 @Nonnull
 ObjIntConsumer<? super byte[]> aConsumer)
                         throws IOException

Throws:

IOException

readUntilEOF

public static void readUntilEOF(@Nonnull @WillClose
 InputStream aIS,
 @Nonnull
 byte[] aBuffer,
 @Nonnull
 ObjIntConsumer<? super byte[]> aConsumer)
                         throws IOException

Throws:

IOException

readUntilEOF

public static void readUntilEOF(@Nonnull @WillClose
 Reader aReader,
 @Nonnull
 ObjIntConsumer<? super char[]> aConsumer)
                         throws IOException

Throws:

IOException

readUntilEOF

public static void readUntilEOF(@Nonnull @WillClose
 Reader aReader,
 @Nonnull
 char[] aBuffer,
 @Nonnull
 ObjIntConsumer<? super char[]> aConsumer)
                         throws IOException

Throws:

IOException

checkForInvalidFilterInputStream

@Nullable
public static InputStream checkForInvalidFilterInputStream(@Nullable
 InputStream aIS)

writeSafeUTF

public static void writeSafeUTF(@Nonnull
 DataOutput aDO,
 @Nullable
 String sStr)
                         throws IOException

Because DataOutputStream.writeUTF(String) has a limit of 64KB this methods provides a similar solution but simply writing the bytes.

Parameters:

aDO - DataOutput to write to. May not be null.

sStr - The string to be written. May be null.

Throws:

IOException - on write error

See Also:

• readSafeUTF(DataInput)

readSafeUTF

@Nullable
public static String readSafeUTF(@Nonnull
 DataInput aDI)
                          throws IOException

Because DataOutputStream.writeUTF(String) has a limit of 64KB this methods provides a similar solution for reading like DataInputStream.readUTF() but what was written in writeSafeUTF(DataOutput, String).

Parameters:

aDI - DataInput to read from. May not be null.

Returns:

The read string. May be null.

Throws:

IOException - on read error

See Also:

• writeSafeUTF(DataOutput, String)