Java FileInputStream和FileOutputStream示例

FileInputStream和FileOutputStream用于从本机文件系统上的文件读取数据并将数据写入。

以下是使用FileInputStream从文件读取数据的示例。

文件：FileInputStreamExample.java –

package com.yiibai.tutorial.io;  import java.io.File; import java.io.FileInputStream; import java.io.IOException;  /**  * @author yiibai  * FileInputStreamExample.java  * Nov 5, 2016  */ public class FileInputStreamExample {     public static void main(String[] args) {         File file=new File("file.txt");         try {             FileInputStream fileInputStream=new FileInputStream(file);             int b;             while((b=fileInputStream.read())!=-1){                 System.out.print((char)b);             }             fileInputStream.close();         } catch (IOException e) {             e.printStackTrace();         }     } } 

执行上面示例代码，得到以下结果：

This is an example of reading data from file. 

以下是使用FileOutputStream将数据写入文件的示例。文件：FileOutputStreamExample.java –

package com.yiibai.tutorial.io;  import java.io.File; import java.io.FileOutputStream; import java.io.IOException;  /**  * @author yiibai  * FileOutputStreamExample.java  * Nov 5, 2016  */ public class FileOutputStreamExample {     public static void main(String[] args) {         String data="This is an example of writing data to a file.";         File file=new File("outfile.txt");         try {             FileOutputStream fileOutputStream = new FileOutputStream(file);             fileOutputStream.write(data.getBytes());             fileOutputStream.close();         } catch (IOException e) {             e.printStackTrace();         }     } } 

执行上面示例代码，得到以下结果：

This is an example of writing data to a file. 

以下程序使用两个文件流将数据从一个文件复制到另一个文件。

文件：FileStreamExample.java –

package com.yiibai.tutorial.io;  import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException;  /**  * @author yiibai  * FileStreamExample.java  * Nov 5, 2016  */ public class FileStreamExample {     public static void main(String[] args) {          File inFile=new File("input.txt");         File outFile=new File("output.txt");          try {             FileInputStream fileInputStream=new FileInputStream(inFile);             FileOutputStream fileOutputStream=new FileOutputStream(outFile);             int i;                 while((i=fileInputStream.read())!=-1){                 fileOutputStream.write(i);             }             fileInputStream.close();             fileOutputStream.close();         } catch (IOException e) {             e.printStackTrace();         }     } } 

输入文件 – input.txt 的内容：

This is an example of the FileInputStream and FileOutputStream. 

输出文件 – output.txt 的内容：

This is an example of the FileInputStream and FileOutputStream.