ViewBuffers.java

package com.brianway.learning.java.nio;//: io/ViewBuffers.java

import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.DoubleBuffer;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.LongBuffer;
import java.nio.ShortBuffer;

/**
 * Created by brian on 16/11/29.
 *
 * 通过在同一个 ByteBuffer 上建立不同的试图缓冲器,
 * 将同一字节序列翻译成short,int,float,long,double等类型的数据
 */

public class ViewBuffers {
    public static void main(String[] args) {
        ByteBuffer bb = ByteBuffer.wrap(
                new byte[] {0, 0, 0, 0, 0, 0, 0, 'a'});
        bb.rewind();
        System.out.print("Byte Buffer ");
        while (bb.hasRemaining())
            System.out.print(bb.position() + " -> " + bb.get() + ", ");
        System.out.println();

        CharBuffer cb =
                ((ByteBuffer) bb.rewind()).asCharBuffer();
        System.out.println("Char Buffer ");
        while (cb.hasRemaining())
            System.out.print(cb.position() + " -> " + cb.get() + ", ");
        System.out.println();

        FloatBuffer fb =
                ((ByteBuffer) bb.rewind()).asFloatBuffer();
        System.out.print("Float Buffer ");
        while (fb.hasRemaining())
            System.out.print(fb.position() + " -> " + fb.get() + ", ");
        System.out.println();

        IntBuffer ib =
                ((ByteBuffer) bb.rewind()).asIntBuffer();
        System.out.print("Int Buffer ");
        while (ib.hasRemaining())
            System.out.print(ib.position() + " -> " + ib.get() + ", ");
        System.out.println();

        LongBuffer lb =
                ((ByteBuffer) bb.rewind()).asLongBuffer();
        System.out.print("Long Buffer ");
        while (lb.hasRemaining())
            System.out.print(lb.position() + " -> " + lb.get() + ", ");
        System.out.println();

        ShortBuffer sb =
                ((ByteBuffer) bb.rewind()).asShortBuffer();
        System.out.print("Short Buffer ");
        while (sb.hasRemaining())
            System.out.print(sb.position() + " -> " + sb.get() + ", ");
        System.out.println();

        DoubleBuffer db =
                ((ByteBuffer) bb.rewind()).asDoubleBuffer();
        System.out.print("Double Buffer ");
        while (db.hasRemaining())
            System.out.print(db.position() + " -> " + db.get() + ", ");
    }
}
/* Output:
Byte Buffer 0 -> 0, 1 -> 0, 2 -> 0, 3 -> 0, 4 -> 0, 5 -> 0, 6 -> 0, 7 -> 97,
Char Buffer 0 ->  , 1 ->  , 2 ->  , 3 -> a,
Float Buffer 0 -> 0.0, 1 -> 1.36E-43,
Int Buffer 0 -> 0, 1 -> 97,
Long Buffer 0 -> 97,
Short Buffer 0 -> 0, 1 -> 0, 2 -> 0, 3 -> 97,
Double Buffer 0 -> 4.8E-322,
*///:~