线程的两种实现方法和进程的两种实现方法。

￡神魔★判官ぃ 2022-09-24 14:22 190阅读 0赞

#     #

# 线程实现 #

## 1. 继承 Thread 类 ##

package com.yuxin.learn;
    
    class MyThread extends Thread{
    	private static int num=0;
    	
    	public MyThread(){
    		num++;
    	}
    
    	@Override
    	public void run() {
    		// TODO Auto-generated method stub
    		System.out.println("主动创建的第"+num+"个方法。");
    		super.run();
    	}
    	
    }
    
    
    public class Main {
    	public static void main(String[] args){
    		System.out.println("主线程："+Thread.currentThread().getId());
    		MyThread thread1 = new MyThread();
    		thread1.start();
    		
    		MyThread thread2 = new MyThread();
    		thread2.run();
    	}
    }

## 2. 实现Runnable接口 ##

package com.yuxin.learn;
    
    class MyRunnable implements Runnable{
    	public MyRunnable(){
    		
    	}
    
    	@Override
    	public void run() {
    		// TODO Auto-generated method stub
    		
    	}
    	
    }
    
    public class Main {
    	public static void main(String[] args){
    		System.out.println("主线程："+Thread.currentThread().getId());
    		MyRunnable myRunnable = new MyRunnable();
    		Thread myThread = new Thread(myRunnable);
    		myThread.start();
    
    	}
    }

# 进程实现 #

## 1. ProcessBuilder ##

ProcessBuilder()->传入的参数保存为List，入参以逗号分割。

package com.yuxin.learn;
    
    import java.io.IOException;
    import java.util.Scanner;
    
    
    public class Main {
    	public static void main(String[] args) throws IOException{
    //		ProcessBuilder pb = new ProcessBuilder("cmd","/c","java -version");
    		ProcessBuilder pb = new ProcessBuilder("cmd","/c","ipconfig/all");
    		Process process = pb.start();
    		Scanner scanner = new Scanner(process.getInputStream());
    		
    		while(scanner.hasNextLine()){
    			System.out.println(scanner.nextLine());
    		}
    		scanner.close();
    	}
    }

## 2. Runtime exec实现 ##

package com.yuxin.learn;
    
    import java.io.IOException;
    import java.util.Scanner;
    
    
    public class Main {
    	public static void main(String[] args) throws IOException{
    		String cmd = "cmd"+" /c"+" arp -a";
    		//Runtime.getRuntime().exec()传入的字符串以空格分隔
    		//exec方法不支持不定长参数（ProcessBuilder是支持不定长参数的）
    		Process process = Runtime.getRuntime().exec(cmd);
    		Scanner scanner = new Scanner(process.getInputStream());
    		
    		while(scanner.hasNextLine()){
    			System.out.println(scanner.nextLine());
    		}
    		scanner.close();
    	}
    }