org.terracotta.utilities.io.buffer

Class DumpUtility

java.lang.Object

org.terracotta.utilities.io.buffer.DumpUtility

public final class DumpUtility
extends Object

Provides methods to dump Buffer instances.

Each instance of this class tracks the buffers it dumps and does not dump the same buffer more than once. Because of this, an instance of this class should not be retained beyond actual need to avoid interfering with garbage collection of the dumped buffers.

Use of Reflection

This class uses reflection to access fields internal to Buffer implementations. Operation of the following methods requires this access:

• dumpBuffer(IntBuffer)
• dumpBuffer(IntBuffer, PrintStream)
• dumpBuffer(LongBuffer)
• dumpBuffer(LongBuffer, PrintStream)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DumpUtility.FieldInaccessibleException Thrown if reflective access to a required internal field fails.

Constructor Summary

Constructors

Constructor and Description
DumpUtility(PrintStream printStream) Constructs a new DumpUtility using the PrintStream provided.
DumpUtility(PrintStream printStream, CharSequence linePrefix) Constructs a new DumpUtility using the PrintStream and line prefix provided.

Method Summary

Modifier and Type	Method and Description
void	dump(byte[] bytes) Writes the contents of byte[] to the PrintStream provided.
void	dumpBuffer(ByteBuffer buffer) Writes the contents of ByteBuffer to the PrintStream provided.
static void	dumpBuffer(ByteBuffer buffer, PrintStream printStream) A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.
void	dumpBuffer(IntBuffer buffer) Attempts to dump a IntBuffer.
static void	dumpBuffer(IntBuffer buffer, PrintStream printStream) A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.
void	dumpBuffer(LongBuffer buffer) Attempts to dump a LongBuffer.
static void	dumpBuffer(LongBuffer buffer, PrintStream printStream) A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

DumpUtility

public DumpUtility(PrintStream printStream)

Constructs a new DumpUtility using the PrintStream provided. This constructor is equivalent to new DumpUtility(printStream, "").

Parameters:

printStream - the PrintStream to which the dump is written

DumpUtility

public DumpUtility(PrintStream printStream,
                   CharSequence linePrefix)

Constructs a new DumpUtility using the PrintStream and line prefix provided.

Parameters:

printStream - the PrintStream to which the dump is written

linePrefix - the value to prepend to each dump line written

Method Detail

dumpBuffer

public static void dumpBuffer(IntBuffer buffer,
                              PrintStream printStream)

A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.

Parameters:

buffer - the IntBuffer to dump

printStream - the PrintStream to which the dump is written

Throws:

UnsupportedOperationException - if the buffer is not a supported type or reflective access to a required field fails

dumpBuffer

public static void dumpBuffer(LongBuffer buffer,
                              PrintStream printStream)

A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.

Parameters:

buffer - the LongBuffer to dump

printStream - the PrintStream to which the dump is written

Throws:

UnsupportedOperationException - if the buffer is not a supported type or reflective access to a required field fails

dumpBuffer

public static void dumpBuffer(ByteBuffer buffer,
                              PrintStream printStream)

A convenience method that allocates a DumpUtility instance, dumps a buffer, and discards the DumpUtility instance.

Parameters:

buffer - the ByteBuffer to dump

printStream - the PrintStream to which the dump is written

dumpBuffer

public void dumpBuffer(IntBuffer buffer)

Attempts to dump a IntBuffer. The present implementation of this method depends the use of ByteBuffer.asIntBuffer in creation of buffer and on the internal implementation of ByteBuffer.

Parameters:

buffer - the IntBuffer instance to dump

Throws:

UnsupportedOperationException - if the buffer is not a supported type or reflective access to a required field fails

dumpBuffer

public void dumpBuffer(LongBuffer buffer)

Attempts to dump a LongBuffer. The present implementation of this method depends the use of ByteBuffer.asLongBuffer in creation of buffer and on the internal implementation of ByteBuffer.

Parameters:

buffer - the LongBuffer instance to dump

Throws:

UnsupportedOperationException - if the buffer is not a supported type or reflective access to a required field fails

dumpBuffer

public void dumpBuffer(ByteBuffer buffer)

Writes the contents of ByteBuffer to the PrintStream provided. The dump consists of a sequence of lines where each line is the dump of a 32-byte segment from the buffer and includes data in hexadecimal and in printable ASCII. A sample dump is shown:

 00000000  00000000 00000000 00000000 00000023  A5000000 00000000 00000000 00000000  *...............# ................*
 00000020  00000000 00000020 00000000 00000023  A5000000 00000000 00000000 00000000  *....... .......# ................*
 00000040-00000C7F  duplicates above                                                 *                                 *
 00000C80  00000000 00000020 00000000 00000351  00000000 00000000 00000000 00000000  *....... .......Q ................*
 00000CA0  00000000 00000000 00000000 00000000  00000000 00000000 00000000 00000000  *................ ................*
 00000CC0-00FFFFDF  duplicates above                                                 *                                 *
 00FFFFE0  00000000 00000000 00000000 00000000  00000000 00000000 00000000 00000000  *................ ................*
 

For a direct ByteBuffer, this method attempts to access the value of an internal field. Failure to access this field does not prevent this method from dumping the ByteBuffer.

Parameters:

buffer - the ByteBuffer to dump; the buffer is printed from position zero (0) through the buffer limit using a view over the buffer

dump

public void dump(byte[] bytes)

Writes the contents of byte[] to the PrintStream provided. The dump consists of a sequence of lines where each line is the dump of a 32-byte segment from the array and includes data in hexadecimal and in printable ASCII. A sample dump is shown:

 00000000  00000000 00000000 00000000 00000023  A5000000 00000000 00000000 00000000  *...............# ................*
 00000020  00000000 00000020 00000000 00000023  A5000000 00000000 00000000 00000000  *....... .......# ................*
 00000040-00000C7F  duplicates above                                                 *                                 *
 00000C80  00000000 00000020 00000000 00000351  00000000 00000000 00000000 00000000  *....... .......Q ................*
 00000CA0  00000000 00000000 00000000 00000000  00000000 00000000 00000000 00000000  *................ ................*
 00000CC0-00FFFFDF  duplicates above                                                 *                                 *
 00FFFFE0  00000000 00000000 00000000 00000000  00000000 00000000 00000000 00000000  *................ ................*
 

Parameters:

bytes - the byte array to dump