Java中io流解析及代码实例

1.FileInputStream/FileOutputStream2.BufferedInputStream/BufferedOutputStream3.SequenceInputStream(序列流)4.ObjectInputStream/ObjectOutputStream(对象的输入输出流)5.PrintStream(打印流)

1.FileReader/FileWriter2.BufferedReader/BufferedWriter3.InputStremReader/OutputStreamWriter(转换流)

·InputStreamReader·OutputStreamWriter

1.装饰对象和真实对象有相同的接口。这样客户端对象就能以和真实对象相同的方式和装饰对象交互2.装饰对象可以在转发这些请求以前或以后增加一些附加功能。这样就确保了在运行时，不用修改给定对象的结构就可以在外部增加附加的功能

package cn.xdian.test;import java/87997.html">java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.SequenceInputStream;import java.util.Enumeration;import java.util.Vector;public class Demo2 {	public static void main(String[] args) throws IOException {		cutFile();		//切割MP3文件		mergeFlile();		//合并MP3文件	}	//合并MP3	public static void mergeFlile() throws IOException{		File dir = new File("/home/gavinzhou/music_test");		//找到文件夹下所有的MP3文件		Vector<FileInputStream> vector = new Vector<FileInputStream>();		File[] files = dir.listFiles();		for (File file : files){			if(file.getName().endsWith(".mp3")){				vector.add(new FileInputStream(file));			}		}		//通过Vector获取迭代器		Enumeration<FileInputStream> e = vector.elements();		//创建序列流		SequenceInputStream inputStream = new SequenceInputStream(e);		//输出流		FileOutputStream fileOutputStream = new FileOutputStream("/home/gavinzhou/conbine.mp3");		//读取分割的MP3文件		byte[] buf = new byte[1024];		int length = 0 ;		while((length = inputStream.read(buf))!=-1){			fileOutputStream.write(buf,0,length);		}		//关闭流		fileOutputStream.close();		inputStream.close();	}	//切割MP3	public static void cutFile() throws IOException{		File file = new File("/home/gavinzhou/test.mp3");		File dir = new File("/home/gavinzhou/music_test");		//输入字节流		FileInputStream fileInputStream = new FileInputStream(file);		//读取文件		byte[] buf = new byte[1024*1024];		int length = 0;		for (int i = 0 ; (length = fileInputStream.read(buf))!=-1 ; i++){			FileOutputStream fileOutputStream = new FileOutputStream(new File(dir,"part"+i+".mp3"));			fileOutputStream.write(buf,0,length);			fileOutputStream.close();		}		//关闭流		fileInputStream.close();	}}

package cn.xidian.test;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;public class Demo1 {	public static void main(String[] args) throws IOException {		File sourceFile = new File("/home/gavinzhou/a.txt");		File desFile = new File("/home/gavinzhou/b.txt");		//创建输入流		BufferedReader input = new BufferedReader(new FileReader(sourceFile));		//创建输出流		BufferedWriter output = new BufferedWriter(new FileWriter(desFile));		//读取源文件,写入到新的文件		String line = null;		while((line = input.readLine()) != null){			output.write(line);			output.newLine();		}		//关闭输入输出流		input.close();		output.close();	}}

package cn.xidian.test;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.PrintStream;/*打印流可以打印任意类型的数据，打印数据之前都会先把数据转换成字符串再进行打印 */class Animal{	String name;	String color;	public Animal(String name,String color){		this.name = name;		this.color = color;	}	@Override	 public String toString() {		return "名字："+this.name+ " 颜色："+ this.color;	}}public class Demo6 {	public static void main(String[] args) throws IOException {		/*  File file = new File("/home/gavinzhou/a.txt");  //创建打印流  PrintStream printStream = new PrintStream(file);  //打印任何信息到文件中  printStream.println(97);  printStream.println(3.14);  printStream.println('a');  printStream.println(true);  Animal a = new Animal("老鼠", "黑色");  printStream.println(a);  //更改标准的输入输出  System.setOut(printStream); //标准输出是到屏幕上  System.out.println("test.......");  */		//收集异常的日志信息。		File logFile = new File("/home/gavinzhou/test.log");		PrintStream logPrintStream = new PrintStream( new FileOutputStream(logFile,true) );		try{			int c = 4/0;			//引起异常			System.out.println("c="+c);			int[] arr = null;			System.out.println(arr.length);		}		catch(Exception e){			e.printStackTrace(logPrintStream);			//输出到文件而不是屏幕上		}	}}