commons.io使用实例-优快云博客

本文链接：https://blog.youkuaiyun.com/iteye_15153/article/details/81885745

本文提供了一系列使用Java进行文件操作的示例代码，包括文件复制、删除及读取文本文件中的每一行内容等。通过这些示例，读者可以了解如何利用Apache Commons IO库来简化常见的文件处理任务。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

1.文件内容拷贝：
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.Writer;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;

publicclass FileCopyExample {
    publicstaticvoid main(String[] args) {
       try {
           File src = new File( "test.dat" );
           File dest = new File( "test.dat.bak" );

           FileUtils.copyFile( src, dest );
       } catch( IOException ioe ) {
           System.out.println( "Problem copying file." );
       }

       try {
           File src = new File( "test.dat" );
           File dir = new File( "./temp" );

           FileUtils.copyFileToDirectory( src, dir );
       } catch( IOException ioe ) {
           System.out.println( "Problem copying file to dir.");
       }

       try {
           String string = "Blah blah blah";
           File dest = new File( "test.tmp" );

           FileUtils.writeStringToFile( dest, string, "ISO-8859-1" );
       } catch( IOException ioe ) {
           System.out.println( "Error writing out a String." );
       }


       try {
           Writer writer = new FileWriter( "test.dat" );
           InputStream inputStream =FileCopyExample.class.
              getClass().getResourceAsStream("/io/web.xml");
           IOUtils.copy( inputStream, writer );
           writer.close();
           inputStream.close();
       } catch (IOException e) {
           System.out.println( "Error copying data" );
       }

try {
           File src = new File( "test.txt" );
           OutputStream output = new FileOutputStream(src);
           InputStream inputStream =FileCopyExample.class.
              getClass().getResourceAsStream("/io/web.xml");
           IOUtils.copy( inputStream, output );
//         writer.close();
           inputStream.close();
           output.close();
       } catch (IOException e) {
           System.out.println( "Error copying data" );
       }
    }

}

2.文件删除：
File file = new File( ("io/project.properties") );
       String display = FileUtils.byteCountToDisplaySize( file.length() );
       System.out.println( "project.xml is " + display );
       FileUtils.forceDelete(file)

3.读取取文本中的每一行：
import java.io.File;
import java.io.IOException;
import java.util.List;

import org.apache.commons.io.FileSystemUtils;
import org.apache.commons.io.FileUtils;

public class Test {

       /**
        * @param args
        * @throws IOException
        */
       public static void main(String[] args) throws IOException {
              // TODO Auto-generated method stub
              File file = new File((Test.class.getClass().getResource("/io/web.xml")).getFile());
               List lines = FileUtils.readLines(file, "UTF-8");
               for(int i=0;i<lines.size();i++)
               System.out.println(lines.get(i));
       }

}