关于synchronized和lock 的使用及其在线程间的通信

题目要求:子线程循环10次，接着主线程循环100次，接着又回到子线程循环10次，接着再
回到主线程又循环100，如此循环50次

synchronized的使用

import java.util.concurrent.atomic.AtomicInteger;

public class TraditionalThreadCommunication {

/**
* @param args
*/
public static void main(String[] args) {

final Business business = new Business();
new Thread(
new Runnable() {

@Override
public void run() {

for(int i=1;i<=50;i++){
business.sub(i);
}

}
}
).start();

for(int i=1;i<=50;i++){
business.main(i);
}

}

}
class Business {
private boolean bShouldSub = true;
public synchronized void sub(int i){
while(!bShouldSub){
try {
this.wait();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
for(int j=1;j<=10;j++){
System.out.println("sub thread sequence of " + j + ",loop of " + i);
}
bShouldSub = false;
this.notify();
}

public synchronized void main(int i){
while(bShouldSub){
try {
this.wait();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
for(int j=1;j<=100;j++){
System.out.println("main thread sequence of " + j + ",loop of " + i);
}
bShouldSub = true;
this.notify();
}
}

lock 和线程间的通信condition：

import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class ConditionCommunication {

/**
* @param args
*/
public static void main(String[] args) {

final Business business = new Business();
new Thread(
new Runnable() {

@Override
public void run() {

for(int i=1;i<=50;i++){
business.sub(i);
}

}
}
).start();

for(int i=1;i<=50;i++){
business.main(i);
}

}

static class Business {
Lock lock = new ReentrantLock();
Condition condition = lock.newCondition();
private boolean bShouldSub = true;
public void sub(int i){
lock.lock();
try{
while(!bShouldSub){
try {
condition.await();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
for(int j=1;j<=10;j++){
System.out.println("sub thread sequence of " + j + ",loop of " + i);
}
bShouldSub = false;
condition.signal();
}finally{
lock.unlock();
}
}

public void main(int i){
lock.lock();
try{
while(bShouldSub){
try {
condition.await();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
for(int j=1;j<=100;j++){
System.out.println("main thread sequence of " + j + ",loop of " + i);
}
bShouldSub = true;
condition.signal();
}finally{
lock.unlock();
}
}

}
}

思考如果变成三个线程一次循环20下 ：这个需要lock和 多个condition进行实现