第八篇 IO流技术（八）

package com.zzp.demo;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

/**
 * 
 * 转换流：InputStreamReader\OutputStreamWrite
 * 1、以字符流的形式操作字节流（纯文本）
 * 2、指定字符集
 * @author java
 *
 */
public class ConvertTest01 {
    public static void main(String[] args) {
        try(BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
                BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(System.out));){
            String msg = "";
            while(!msg.equals("exit")){
                msg = reader.readLine();//循环读取
                writer.write(msg);//循环写出
                writer.newLine();
                writer.flush();//强制刷新
            }
        } catch (Exception e) {
            System.out.println("异常"+e);
        }
    }
}

package com.zzp.demo;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URL;

/**
 * 
 * 转换流：InputStreamReader\OutputStreamWrite
 * 1、以字符流的形式操作字节流（纯文本）
 * 2、指定字符集
 * @author java
 *
 */
public class ConvertTest02 {
    public static void main(String[] args) {
        test03();
    }
    
    public static void test01(){
        try(InputStream is = new URL("http://www.baidu.com").openStream();){
            int temp;
            while((temp = is.read()) != -1){
                System.out.print((char)temp);
            }
        } catch (Exception e) {
            System.out.println("异常"+e);
        }
    }
    
    public static void test02(){
        try(InputStreamReader isr = new InputStreamReader(
                new URL("http://www.baidu.com").openStream(),"UTF-8");){
            int temp;
            while((temp = isr.read()) != -1){
                System.out.print((char)temp);
            }            
        } catch (Exception e) {
            System.out.println("异常："+e);
        }
    }
    
    public static void test03(){
        try(BufferedReader reader = new BufferedReader(
                new InputStreamReader(
            new URL("http://www.baidu.com").openStream(),"UTF-8"));
                BufferedWriter writer = new BufferedWriter(
                    new OutputStreamWriter(
                            new FileOutputStream("baidu.html"),"UTF-8"))){
            String msg;
            while((msg=reader.readLine())!=null){
                writer.write(msg);
                writer.newLine();
            }
            writer.flush();
        } catch (Exception e) {
            System.out.println("异常" + e);
        }
    }
}

 

package com.zzp.demo;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.IOException;

/**
 * 
 * 数据流
 * 1、写出后读取
 * 2、读取的顺序和写出后一致
 * DataoutputStream
 * DatainputStream
 * @author java
 *
 */
public class DataTest {
    public static void main(String[] args) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(baos));
        dos.writeUTF("这小子真帅");
        dos.writeInt(12);
        dos.writeBoolean(false);
        dos.writeByte('a');
        dos.flush();
        byte[] byteArray = baos.toByteArray();
        System.out.println(byteArray.length);
        
        DataInputStream dis = new DataInputStream(
                new BufferedInputStream(new ByteArrayInputStream(byteArray)));    
        String readUTF = dis.readUTF();
        int readInt = dis.readInt();
        boolean readBoolean = dis.readBoolean();
        byte readByte = dis.readByte();
        System.out.println(readUTF);
    }
}

 对象流

package com.zzp.demo;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Date;

/**
 * 
 * 对象流:
 * 1、写出后读取
 * 2、读取的顺序与写出保持一致
 * 3、不是所有的对象都可以序列化Serializable
 * ObjectOutputStream
 * ObjectInputStream
 * @author java
 *
 */
public class ObjectTest {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ObjectOutputStream dos = new ObjectOutputStream(new BufferedOutputStream(baos));
        dos.writeUTF("这小子真帅");
        dos.writeInt(12);
        dos.writeBoolean(false);
        dos.writeByte('a');
        //对象
        dos.writeObject("人生没有什么是大不了的");
        dos.writeObject(new Date());
        dos.writeObject(true);
        dos.writeObject(new Employee("张三", 400));
        dos.flush();
        byte[] byteArray = baos.toByteArray();
        System.out.println(byteArray.length);
        
        ObjectInputStream dis = new ObjectInputStream(
                new BufferedInputStream(new ByteArrayInputStream(byteArray)));    
        String readUTF = dis.readUTF();
        int readInt = dis.readInt();
        boolean readBoolean = dis.readBoolean();
        byte readByte = dis.readByte();
        System.out.println(readUTF);
        
        Object str = dis.readObject();
        Object date = dis.readObject();
        Object blo = dis.readObject();
        Object emp = dis.readObject();
        if(str instanceof String){
            String strObj = (String)str;
            System.out.println(strObj);
        }
        
        if(date instanceof Date){
            Date dateObj = (Date)date;
            System.out.println(dateObj);
        }
        
        if(blo instanceof Boolean){
            Boolean bloObj = (Boolean)blo;
            System.out.println(bloObj);
        }
        
        if(emp instanceof Employee){
            Employee empObj = (Employee)emp;
            System.out.println(empObj.getName()+"---"+empObj.getSalary());
        }
    }
}

class Employee implements java.io.Serializable{
    private transient String name;//该数据不需要序列化
    private double salary;
    public Employee(String name, double salary) {
        super();
        this.name = name;
        this.salary = salary;
    }
    public Employee() {
        super();
        // TODO Auto-generated constructor stub
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public double getSalary() {
        return salary;
    }
    public void setSalary(double salary) {
        this.salary = salary;
    }
}

 

package com.zzp.demo;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Date;

/**
 * 
 * 对象流:
 * 1、写出后读取
 * 2、读取的顺序与写出保持一致
 * 3、不是所有的对象都可以序列化Serializable
 * ObjectOutputStream
 * ObjectInputStream
 * @author java
 *
 */
public class ObjectTest02 {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        ObjectOutputStream dos = new ObjectOutputStream(new BufferedOutputStream(new FileOutputStream("3.txt")));
        dos.writeUTF("这小子真帅");
        dos.writeInt(12);
        dos.writeBoolean(false);
        dos.writeByte('a');
        //对象
        dos.writeObject("人生没有什么是大不了的");
        dos.writeObject(new Date());
        dos.writeObject(true);
        dos.writeObject(new Employee("张三", 400));
        dos.flush();
        dos.close();
        
        ObjectInputStream dis = new ObjectInputStream(
                new BufferedInputStream(new FileInputStream("3.txt")));    
        String readUTF = dis.readUTF();
        int readInt = dis.readInt();
        boolean readBoolean = dis.readBoolean();
        byte readByte = dis.readByte();
        System.out.println(readUTF);
        
        Object str = dis.readObject();
        Object date = dis.readObject();
        Object blo = dis.readObject();
        Object emp = dis.readObject();
        if(str instanceof String){
            String strObj = (String)str;
            System.out.println(strObj);
        }
        
        if(date instanceof Date){
            Date dateObj = (Date)date;
            System.out.println(dateObj);
        }
        
        if(blo instanceof Boolean){
            Boolean bloObj = (Boolean)blo;
            System.out.println(bloObj);
        }
        
        if(emp instanceof Employee){
            Employee empObj = (Employee)emp;
            System.out.println(empObj.getName()+"---"+empObj.getSalary());
        }
        dis.close();
    }
}