IO

Commons IO is a library of utilities to assist with developing IO functionality. There are four main areas

included: 

 ●Utility classes - with static methods to perform common tasks 

 ●Filters - various implementations of file filters 

 ●Comparators - various implementations of java.util.Comparator for files

 ●Streams - useful stream, reader and writer implementations

 

通过IOUtils 我们能够提升IO读写效率。下面是一些简单分析。

 

IOUtils 输入流复制到 输出流

Writer write = new FileWriter("c:\kk.dat");  

InputStream ins = new FileInputStream(new File("c:\text.txt"));  
 
IOUtils.copy(ins, write);  

ins.close(); write.close();

copy(InputStream in, OutputStream out )的实现

    public static long copyLarge(final InputStream input, final OutputStream output, final byte[] buffer)
            throws IOException {
        long count = 0;
        int n;
        while (EOF != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }

可以发现，copy流的方法直接写入而不仅仅是定义OutputStream，这点开发中一定要注意。 ^_^

IOUtils的closeQuietly()方法:

　　Unconditionally close an InputStream.

　　Equivalent to InputStream.close(), except any exceptions will be ignored. This is typically used in finally blocks.