做房产网站赚钱吗,中国建设积分商城网站,iis7.5网站配置,网站seo设置是什么此文介绍nio中ByteBuffer的特性之一,视图. *view buffer概念 ---把ByteBuffer转换为其他数据类型的buffer,比如char,long,float等,这样就方便处理连续的多字节情况 ---相关的api,形如as*Buffer,如LongBuffer asLongBuffer()之类 *功能特性(ByteBuffer注释中views条…此文介绍nio中ByteBuffer的特性之一,视图. *view buffer概念 ---把ByteBuffer转换为其他数据类型的buffer,比如char,long,float等,这样就方便处理连续的多字节情况 ---相关的api,形如as*Buffer,如LongBuffer asLongBuffer()之类 *功能特性(ByteBuffer注释中views条目有详细的注解) ---视图和原ByteBuffer共享数据,但各自独立位置信息. Changes to the byte buffers contentwill be visible in the view buffer, and vice versa; the two buffersposition, limit, and mark values are independent. ---view buffer的字节次序在创建时被确定 The byte order of a view buffer is fixed to be that of its byte bufferat the time that the view is created. ---优点 方便处理大块数据 *api分析 以子类HeapByteBuffer中的实现方式为例,其他类型的实现方式相同 CharBuffer java.nio.HeapByteBuffer.asCharBuffer()public CharBuffer asCharBuffer() {int size this.remaining() 1; //char比byte多一个字节,容量int off offset position(); //offset从原buffer的position开始return (bigEndian? (CharBuffer)(new ByteBufferAsCharBufferB(this, //与原buffer共享数据-1, //mark -10, //position 0size, //limit sizesize, //compacity sizeoff)) //offset off: (CharBuffer)(new ByteBufferAsCharBufferL(this,-1,0,size,size,off)));
}
/*
*1.view buffer的数据内容是原buffer的remaining部分
*2.view buffer和原buffer保持相同的字节顺序
*/ *测试示例 示例ViewBufferTest/*** Feb 16, 2011 by dzh*/
package buffer.view;import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.CharBuffer;/*** author dzh**/
public class ViewBufferTest {public static void main(String[] args) {ByteBuffer byteBuf ByteBuffer.allocate(6).order(ByteOrder.BIG_ENDIAN);byteBuf.put((byte) 0).put((byte) A).mark();byteBuf.put(new byte[]{0,B,0,C}).reset();CharBuffer charBuf byteBuf.asCharBuffer();System.out.println(byteBuf.toString()); //java.nio.HeapByteBuffer[pos2 lim6 cap6]System.out.println(charBuf.toString()); //BC}} 转载于:https://www.cnblogs.com/bronte/articles/1955914.html
