易百教程

FileReader和FileWriter分别是用于读写字符文件的便捷类。 FileReader和FileWriter类都使用系统的默认编码。

以下示例显示了FileReader和FileWriter的用法。

文件：FileReaderWriterExample.java -

package com.yiibai.tutorial.io;

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

/**
 * @author yiibai
 */
public class FileReaderWriterExample {
    public static void main(String[] args) {
        File file = new File("file.txt");

        /* Writing File Using FileWriter */
        FileWriter fileWriter = null;
        try {
            fileWriter = new FileWriter(file);
            fileWriter.write("This is an example of using");
            fileWriter.write(" FileReader and ");
            fileWriter.write(" FileWriter. ");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (fileWriter != null) {
                    fileWriter.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        /* Reading File Using FileReader */
        FileReader fileReader = null;
        try {
            fileReader=new FileReader(file);
            char ch[]=new char[20];
            int i=0;
            while((i=fileReader.read(ch))!=-1){
                System.out.println(new String(ch,0,i));
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            try {
                if (fileReader != null) {
                    fileReader.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

执行上面示例代码，得到以下结果：

This is an example o
f using FileReader a
nd  FileWriter.