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Java lang extensions for java6+, a supplement to , replacement of a Guava, commons-lang. Core utilities, Collection utilities, IO utilities, Cache, Configuration library ...

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package com.jn.langx.util.io;


import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;


/**
 * A serializable object which implements a simple, efficient, serialization
 * protocol, based on {@link DataInput} and {@link DataOutput}.
 * 
 * 
Any key or value type in the Hadoop Map-Reduce
 * framework implements this interface.
 * 
 * 
Implementations typically implement a static read(DataInput)
 * method which constructs a new instance, calls {@link #readFields(DataInput)}
 * and returns the instance.
 * 
 * 
Example:
 * 
 *     public class MyWritable implements Writable {
 *       // Some data
 *       private int counter;
 *       private long timestamp;
 * 
 *       public void write(DataOutput out) throws IOException {
 *         out.writeInt(counter);
 *         out.writeLong(timestamp);
 *       }
 * 

 *       public void readFields(DataInput in) throws IOException {
 *         counter = in.readInt();
 *         timestamp = in.readLong();
 *       }
 * 

 *       public static MyWritable read(DataInput in) throws IOException {
 *         MyWritable w = new MyWritable();
 *         w.readFields(in);
 *         return w;
 *       }
 *     }
 * 

 */
public interface Writable {
    /**
     * Serialize the fields of this object to out.
     *
     * @param out DataOuput to serialize this object into.
     * @throws IOException
     */
    void write(DataOutput out) throws IOException;

    /**
     * Deserialize the fields of this object from in.
     * 
     * 
For efficiency, implementations should attempt to re-use storage in the
     * existing object where possible.
     *
     * @param in DataInput to deseriablize this object from.
     * @throws IOException
     */
    void readFields(DataInput in) throws IOException;
}