Java基础学习笔记4

（20160111）

【扣丁学堂】

Test13 缓存流

package practice06;
//缓存流

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;

public class Test13 {
	
	public static void charStreamOut(){
		try {
			Writer out=new FileWriter("f:\\a.txt");
			BufferedWriter bw=new BufferedWriter(out);
			bw.write("让编程更简单");
			bw.close();
			out.close();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static void charStreamIn(){
		try {
			Reader in =new FileReader("f:\\a.txt");
			BufferedReader br=new BufferedReader(in);
			String info=br.readLine();
			System.out.println(info);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static void byteStreamOut(){
		try {
			OutputStream out=new FileOutputStream("f:\\a.txt");
			//让字节输出流具备缓冲功能
			BufferedOutputStream bos=new BufferedOutputStream(out);
			bos.write("让编程更简单".getBytes());
			bos.close();
			out.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static void byteStreamIn(){
		try {
			InputStream in =new FileInputStream("f:\\a.txt");
			BufferedInputStream bis=new BufferedInputStream(in);
			byte[]bytes=new byte[1024];
			int len=-1;
			StringBuffer buf=new StringBuffer();
			while((len=bis.read(bytes))!=-1){
				buf.append(new String(bytes,0,len));
			}
			bis.close();
			in.close();
			System.out.println(buf);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static void main(String[] args) {
	//	byteStreamIn();
	//	byteStreamOut();
		charStreamIn();
		charStreamOut();
	}
}

Test14 打印流

package practice06;

import java.io.BufferedOutputStream;
import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.Writer;

//打印流
public class Test14 {
	public static void printStream(){
		//
	}
	public static void charStreamOut(){
		try {
			Writer out=new FileWriter("f:\\a.txt");
			BufferedWriter bw=new BufferedWriter(out);
			PrintWriter pw=new PrintWriter(bw);
			pw.println(97);
			pw.println("abc");
			pw.println(true);
	//		bw.write("让编程更简单");
			bw.close();
			out.close();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static void byteStreamOut(){
		try {
			OutputStream out=new FileOutputStream("f:\\a.txt");
			//让字节输出流具备缓冲功能
			BufferedOutputStream bos=new BufferedOutputStream(out);
			PrintStream ps=new PrintStream(bos);
//			bos.write("让编程更简单".getBytes());
			ps.println(123);
			ps.println("abc");
			ps.println(true);
			bos.close();
			out.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static void main(String[] args) {
		byteStreamOut();
		charStreamOut();
	}
}

Test15 字节数组流 数据流 字符串流

package practice06;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringReader;

import org.omg.CORBA.PUBLIC_MEMBER;


public class Test15 {
	//字节数组流,没有操作文件(了解)
	public static void byteArraysStream(){
		String info="让编程更简单";
		ByteArrayInputStream bis=new ByteArrayInputStream(info.getBytes());
		ByteArrayOutputStream bos=new ByteArrayOutputStream();
		int i=-1;
		while((i=bis.read())!=-1){
			bos.write(i);
		}
		System.out.println(bos.toString());
	}
	//数据流(掌握)
	public static void DataOut() {
		try {
			OutputStream out = new FileOutputStream("f:\\a.txt");
			DataOutputStream dos=new DataOutputStream(out);
			dos.writeInt(10);//写入4个字节
			dos.writeUTF("学堂");
			dos.writeLong(1232434556);
			dos.close();
			out.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
	public static void DataIn(){
		try {
			InputStream in = new FileInputStream("f:\\a.txt");
			DataInputStream dis=new DataInputStream(in);
			int a=dis.readInt();
			String s=dis.readUTF();
			long b=dis.readLong();
			System.out.println(a+s+b);
			dis.close();
			in.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
	//字符串流StringReader StringWriter
	public static void stringStream(){
		String info="让编程更简单";
		StringReader reader=new StringReader(info);
		
	}
	public static void main(String[] args) {
//		byteArraysStream();
		DataOut();
		DataIn();
	}
}

Test16 RandomAccessFile

package practice06;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;

public class Test16 {
	public static void main(String[] args) {
		try {
			File file=new File("f:\\a.txt");
			RandomAccessFile raf=new RandomAccessFile(file, "rw");
			raf.writeInt(18);
			raf.writeUTF("小弱");
			raf.writeBoolean(false);
			raf.writeChar('女');
			raf.seek(0);//定位到文件的开始位置
			int age=raf.readInt();
			String name=raf.readUTF();
	//		raf.seek(1);
			raf.skipBytes(1);//跳过一个字节
			char sex=raf.readChar();
			System.out.println("age="+age+" name="+name+" sex="+sex);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

}

Test17 字体转换

package practice06;

import java.io.UnsupportedEncodingException;

public class Test17 {
	public static void main(String[] args) {
		String name = "让编程更简单";
		try {
			String name1=new String(name.getBytes("GBK"),"iso-8859-1");
			System.out.println(name1);
			String name2=new String(name1.getBytes("iso-8859-1"),"GBK");
			System.out.println(name2);
		} catch (UnsupportedEncodingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
}