Module com.aoapps.lang

Package com.aoapps.lang.io

Class FastObjectOutput

java.lang.Object

com.aoapps.lang.io.FastObjectOutput

All Implemented Interfaces:

DataOutput, ObjectOutput, AutoCloseable

public class FastObjectOutput
extends Object
implements ObjectOutput

Utilities to write FastExternalizable, Externalizable, and Serializable objects.

When multiple objects are being written, this avoids the repetitive writing of classnames and serialVersionUIDs.

Author:

AO Industries, Inc.

Method Summary

Modifier and Type	Method	Description
void	close()
void	flush()
void	unwrap()	Unwraps the object output.
static FastObjectOutput	wrap(ObjectOutput out)	Gets the wrapper for the provided ObjectOutput, creating if needed.
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)
void	writeBoolean(boolean v)
void	writeByte(int v)
void	writeBytes(String s)
void	writeChar(int v)
void	writeChars(String s)
void	writeDouble(double v)
protected void	writeFastObject(FastExternalizable obj)	Writes a FastExternalizable object to the provided stream, supporting null values.
void	writeFastUTF(String value)	Writes a String to the output, not writing any duplicates.
void	writeFloat(float v)
void	writeInt(int v)
void	writeLong(long v)
void	writeObject(Object obj)	Writes the provided object in the most efficient manner possible, with no object graph tracking (if possible).
void	writeShort(int v)
void	writeUTF(String s)

Methods inherited from class java.lang.Object

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

Method Details

wrap

public static FastObjectOutput wrap(ObjectOutput out)
                             throws IOException

Gets the wrapper for the provided ObjectOutput, creating if needed. To avoid memory leaks, it must also be unwrapped in a finally block.

TODO: Can FastObjectOutput itself implement AutoCloseable for unwrap()? Maybe this means it no longer implements ObjectOutput directly?

Throws:

IOException

unwrap

public void unwrap()
            throws IllegalStateException

Unwraps the object output.

Throws:

IllegalStateException - if not wrapped

writeObject

public void writeObject(Object obj)
                 throws IOException

Writes the provided object in the most efficient manner possible, with no object graph tracking (if possible). This allows individual objects to switch between FastExternalizable and standard serialization without calling code needing to know the difference.

If the object is null, writes a single byte of NULL.

If the object is FastExternalizable, calls writeFastObject(com.aoapps.lang.io.FastExternalizable).

Otherwise, writes STANDARD and then uses standard Java serialization.

Specified by:

writeObject in interface ObjectOutput

Throws:

IOException

See Also:

• FastObjectInput.readObject()

writeFastObject

protected void writeFastObject(FastExternalizable obj)
                        throws IOException

Writes a FastExternalizable object to the provided stream, supporting null values.

Throws:

IOException

See Also:

• FastObjectInput.readFastObject(int)

writeFastUTF

public void writeFastUTF(String value)
                  throws IOException

Writes a String to the output, not writing any duplicates. Supports null.

TODO: Any benefit to string prefix compression, like in CompressedDataOutput?

Throws:

IOException

write

public void write(int b)
           throws IOException

Specified by:

write in interface DataOutput

Specified by:

write in interface ObjectOutput

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Specified by:

write in interface DataOutput

Specified by:

write in interface ObjectOutput

Throws:

IOException

write

public void write(byte[] b,
 int off,
 int len)
           throws IOException

Specified by:

write in interface DataOutput

Specified by:

write in interface ObjectOutput

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface ObjectOutput

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface ObjectOutput

Throws:

IOException

writeBoolean

public void writeBoolean(boolean v)
                  throws IOException

Specified by:

writeBoolean in interface DataOutput

Throws:

IOException

writeByte

public void writeByte(int v)
               throws IOException

Specified by:

writeByte in interface DataOutput

Throws:

IOException

writeShort

public void writeShort(int v)
                throws IOException

Specified by:

writeShort in interface DataOutput

Throws:

IOException

writeChar

public void writeChar(int v)
               throws IOException

Specified by:

writeChar in interface DataOutput

Throws:

IOException

writeInt

public void writeInt(int v)
              throws IOException

Specified by:

writeInt in interface DataOutput

Throws:

IOException

writeLong

public void writeLong(long v)
               throws IOException

Specified by:

writeLong in interface DataOutput

Throws:

IOException

writeFloat

public void writeFloat(float v)
                throws IOException

Specified by:

writeFloat in interface DataOutput

Throws:

IOException

writeDouble

public void writeDouble(double v)
                 throws IOException

Specified by:

writeDouble in interface DataOutput

Throws:

IOException

writeBytes

public void writeBytes(String s)
                throws IOException

Specified by:

writeBytes in interface DataOutput

Throws:

IOException

writeChars

public void writeChars(String s)
                throws IOException

Specified by:

writeChars in interface DataOutput

Throws:

IOException

writeUTF

public void writeUTF(String s)
              throws IOException

Specified by:

writeUTF in interface DataOutput

Throws:

IOException