java装饰设计模式------缓冲流

来源：互联网发布：如何搭建阿里云服务器编辑：程序博客网时间：2024/05/16 18:15

小弟不才，最近在做一个压缩文件的方法，读写效率慢让我为之头疼，于是在网上查了很多资料，才发现缓冲流（很惭愧，学了几年java了居然才用到缓冲流），于是记录下来，希望以后不要再犯此类错误。

废话不多说了，先看测试结果

首先copy一个文件，文件大约为91.9 M

接下来看加缓冲和不添加缓冲的效果

不添加缓冲的

</pre><pre name="code" class="java">public void copy(String inputName,String outName){FileInputStream inputStream=null;FileOutputStream outputStream=null;try {inputStream=new FileInputStream(new File(inputName));outputStream=new FileOutputStream(new File(outName));int BUFFERSIZE = 2 << 10;int len=0;byte[] buffer=new byte[BUFFERSIZE];while((len=inputStream.read())!=-1){//outputStream.write(buffer, 0, len);outputStream.write(len);}} catch (Exception e) {e.printStackTrace();}finally{try {inputStream.close();outputStream.close();} catch (IOException e) {e.printStackTrace();}}}

测试结果是292517毫秒

增加缓冲的

public void copy(String inputName,String outName){FileInputStream inputStream=null;FileOutputStream outputStream=null;try {inputStream=new FileInputStream(new File(inputName));outputStream=new FileOutputStream(new File(outName));int BUFFERSIZE = 2 << 10;int len=0;byte[] buffer=new byte[BUFFERSIZE];while((len=inputStream.read(buffer,0,BUFFERSIZE))!=-1){outputStream.write(buffer, 0, len);//outputStream.write(len);}} catch (Exception e) {e.printStackTrace();}finally{try {inputStream.close();outputStream.close();} catch (IOException e) {e.printStackTrace();}}}

测试结果是323毫秒

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