1.線程的基本概念

2.線程的創(chuàng)建

3.線程的調(diào)度和優(yōu)先級(jí)

4.線程的狀態(tài)控制

5.線程同步

           void setPriority();

                 涉及優(yōu)先級(jí)的demo(線程優(yōu)先級(jí)越高，分配的時(shí)間片相對(duì)越長(zhǎng))：    

public class TestPriority {    public static void main(String[] args) {		Runnable runnable1=new T1();		Runnable runnable2=new T2();		Thread thread1=new Thread(runnable1);		Thread thread2=new Thread(runnable2);		thread1.setPriority(Thread.NORM_PRIORITY+3);		thread1.start();		thread2.start();	}}class T1 implements Runnable{	public void run() {		for(int i=0;i<1000;i++){			System.out.println("T1: "+i);		}	}	}class T2 implements Runnable{	public void run() {		for(int i=0;i<1000;i++){			System.out.println("T2: "+i);		}	}	}
4.1 線程狀態(tài)控制
4.1.1 sleep()方法 (讓當(dāng)前線程休眠)(如何優(yōu)雅地關(guān)掉一個(gè)線程 interrupt、stop、通過標(biāo)志位【推薦】)        
import java.util.Date;/*sleep用法*/public class TestInterrupted {	public static void main(String[] args) {		Runnable thread = new Mythread1();// 創(chuàng)建線程		Thread mythread=new Thread(thread);		mythread.start();// 使線程處于就緒狀態(tài)		try {			Thread.sleep(10000);		} catch (InterruptedException e) {		}		mythread.interrupt();	}}/* * 推薦使用--通過實(shí)現(xiàn)接口來實(shí)現(xiàn)Thread的創(chuàng)建  * 1.1 java里面只有單繼承，這樣線程類的靈活性更好 */class Mythread1 implements Runnable{	public void run() {		while(true) {			System.out.println("---" + new Date() + "---");			try {				Thread.sleep(1000);			} catch (InterruptedException e) {				// 捕捉到異常時(shí)退出				return;			}		}	}}              
                **如何優(yōu)雅關(guān)閉一個(gè)線程：
public class TestThread1 {	public static void main(String[] args) {		Runner1 runner1=new Runner1();		Thread thread=new Thread(runner1);		thread.start();		for(int i=0;i<100000;i++){			if(i%10000==0&&i>0){				System.out.println("in main thread i="+i);			}		}		System.out.println("thread main is over");		//thread.stop();  //不推薦使用stop()		runner1.shutDown();	}}class Runner1 implements Runnable{	//如何地優(yōu)雅關(guān)閉某個(gè)線程：實(shí)質(zhì)就是優(yōu)雅停止執(zhí)行線程的方法體：run()	private boolean flag=true;	public void run() {		int i=0;		while(flag==true){			System.out.println("i: "+i++);		}	}		public void shutDown(){		flag=false;	}	}
4.1.2 join()方法  (合并某個(gè)線程)
public class TestJoin {	public static void main(String[] args) {		Runnable runnable=new Mythread2();		Thread thread=new Thread(runnable);		thread.setName("thread1");		thread.start();		try {			thread.join();		} catch (InterruptedException e) {			e.printStackTrace();		}		for(int i=1;i<=10;i++){			System.out.println("i am main thread");		}	}    }class  Mythread2 implements Runnable{	public void run() {		for(int i=1;i<=10;i++){			System.out.println("i am "+Thread.currentThread().getName());			try {				Thread.sleep(1000);			} catch (InterruptedException e) {				e.printStackTrace();			}		}	}	}
4.1.3 yield()方法 (讓出cpu,給其他線程執(zhí)行的機(jī)會(huì))
public class TestYield {    public static void main(String[] args) {		Runnable runnable=new MyThread3();		Thread thread1=new Thread(runnable);		Thread thread2=new Thread(runnable);		thread1.start();		thread2.start();		for(int i=0;i<20;i++){			System.out.println("mainThread"+": "+i);			if(i%10==0){				Thread.yield();			}		}	}}class MyThread3 implements Runnable{	@Override	public void run() {        for(int i=0;i<20;i++){        	System.out.println(Thread.currentThread().getName()+": "+i);        	if(i%10==0){        		Thread.yield();        	}        }	}	}
4.1.4 wait()方法 、notify()/notifyAll()方法(配對(duì)使用、前提：獲得鎖)
                        wait():     
           
                        notify():
                        經(jīng)典的消費(fèi)者生產(chǎn)者問題：
public class ProductComsumer {  public static void main(String[] args) {	SyncStack stack=new SyncStack();	Producter producter=new Producter(stack);	Comsumer comsumer=new Comsumer(stack);	new Thread(producter).start();	new Thread(comsumer).start();}}//饅頭類class WoTou{	private int id;	public WoTou(int id){		this.id=id;	}	public String toString(){		return "WoTou : "+id;	}}//蒸籠類class SyncStack{	private int index=0;	private WoTou[] arrWT=new WoTou[6];		//生產(chǎn)饅頭	public synchronized void push(WoTou wt){		while(index==arrWT.length){			try {				this.wait();  //停止生產(chǎn)饅頭			} catch (InterruptedException e) {				e.printStackTrace();			}		}		this.notify();     //通知消費(fèi)饅頭		arrWT[index]=wt;		index++;	}	//消費(fèi)饅頭	public synchronized WoTou pop(){		while(index==0){			try {				this.wait();  //停止消費(fèi)饅頭			} catch (InterruptedException e) {				e.printStackTrace();			}		}		this.notify();    //通知生產(chǎn)饅頭		index--;		return arrWT[index];	}}//生產(chǎn)者類class Producter implements Runnable{	    private SyncStack stack=null;    public Producter(SyncStack stack){    	this.stack=stack;    }	public void run() {		WoTou woTou=null;	   for(int i=0;i<20;i++){			   woTou=new WoTou(i);		   stack.push(woTou);		   System.out.println("生產(chǎn)了："+woTou);		   try {			Thread.sleep((int)Math.random()*1000);		} catch (InterruptedException e){			e.printStackTrace();		}	   }	}	}//消費(fèi)者類class Comsumer implements Runnable{	  private SyncStack stack=null;  public Comsumer(SyncStack stack){  	this.stack=stack;  }	public void run() {		WoTou woTou=null;	   for(int i=0;i<20;i++){			   woTou=stack.pop();		   System.out.println("消費(fèi)了："+woTou);		   try {				Thread.sleep((int)Math.random()*1000);			} catch (InterruptedException e){				e.printStackTrace();			}	   }	}	}
5.1 線程同步      5.1.1 當(dāng)用synchronized來修飾一個(gè)方法或代碼塊的時(shí)候，能夠保證在同一時(shí)刻最多只能只有     一個(gè)線程執(zhí)行該段代碼      5.1.2 當(dāng)兩個(gè)并發(fā)線程訪問同一對(duì)象object中的這個(gè)synchronized(this)同步代碼塊時(shí)，一個(gè)時(shí)間內(nèi)      只能有一個(gè)線程得到執(zhí)行。另外一個(gè)線程必須等待當(dāng)前線程執(zhí)行完這個(gè)代碼塊以后才能執(zhí)行該代碼塊      5.1.3 當(dāng)一個(gè)線程訪問object的一個(gè)synchronized(this)同步代碼塊時(shí)，另一個(gè)線程仍然可以訪問該      object的非synchronized(this)同步代碼塊      5.1.4 *當(dāng)一個(gè)線程訪問object的一個(gè)synchronize(this)代碼塊，其他線程對(duì)該object中所有其他      synchronized(this)同步代碼塊的訪問將被阻塞      5.1.5 synchronized同步方法、synchronized同步方法塊      5.1.6 死鎖就是指多個(gè)進(jìn)程(線程)因競(jìng)爭(zhēng)資源(系統(tǒng)資源競(jìng)爭(zhēng)、程序推進(jìn)順序非法)而造成的一種僵局
      5.1.7 死鎖產(chǎn)生的必要條件：互斥條件、不可剝奪條件、請(qǐng)求和保持條件、循環(huán)等待鏈條件
             
               線程同步demo:
public class TestSync implements Runnable { 	Timer timer=new Timer();		public static void main(String[] args) {       TestSync test=new TestSync();       Thread thread1=new Thread(test);       Thread thread2=new Thread(test);       thread1.setName("t1");       thread2.setName("t2");       thread1.start();       thread2.start();	}	public void run() {       timer.add(Thread.currentThread().getName());	}}class Timer {	private static int num = 0;	public void add(String name) {		synchronized (this) {			num++;			try {				Thread.sleep(1);			} catch (InterruptedException e) {							}			System.out.println(name + ",你是第" + num + "個(gè)使用timer的線程");		}	}}               線程死鎖：
public class DeadLock {	public static void main(String[] args) {		Object o1 = new Object();		Object o2 = new Object();				Thread t1 = new T1(o1,o2);		Thread t2 = new T2(o1,o2);				t1.start();		t2.start();	}}class T1 extends Thread{		Object o1;	Object o2;		T1(Object o1,Object o2){		this.o1 = o1;		this.o2 = o2;	}		public void run() {		synchronized (o1) {			try {				Thread.sleep(1000);			} catch (InterruptedException e) {				e.printStackTrace();			}			synchronized (o2) {							}		}	}}class T2 extends Thread{		Object o1;	Object o2;		T2(Object o1,Object o2){		this.o1 = o1;		this.o2 = o2;			}		public void run() {		synchronized (o2) {			synchronized (o1) {							}		}	}}               經(jīng)典多線程面試題
public class TT implements Runnable{	private int b=100;		public synchronized void m1() throws Exception{		b=1000;		Thread.sleep(5000);		System.out.println("b = "+b);	}//       1.	public void m2() throws Exception{		Thread.sleep(2500);		b=2000;	}	//       2.//		public synchronized void m2() throws Exception{//			Thread.sleep(2500);//			b=2000;//		}	public void run() {		try {			m1();		} catch (Exception e) {			e.printStackTrace();		}	}    public static void main(String[] args) throws Exception{		TT tt=new TT();		Thread t=new Thread(tt);		t.start();		tt.m2();		System.out.println(tt.b);    }	}