架构师成长之旅第一篇

日常积累

线程的状态：

状态	解释
NEW	新建状态，尚未启动状态
RUNNABLE	就绪状态 正在运行或者是排队等待CPU给它分配资源
BLOCKED	阻塞等待锁的状态，等待监视器锁，比如等待执行synchronized代码块或者使用synchronized标记的方法
WAITING	等待状态，正在等待另一个线程执行某个特定的动作，比如调用了Object.wait()方法，等待另一个线程调用Object.notify()或者notifyAll()方法
TIMED_WAITING	计时等待状态 比如调用了Object.wait(long timeout)和Thread.join(long timeout)等这些方法时，它才会进入此状态
TERMINATED	终止状态，执行完毕

线程状态源代码如下：

public enum State{
		NEW,RUNNABLE,BLOCKED,WAITING,TIMED_WAITING,TERMINATED,
}

Runnable的run方法和Thread的start方法区别

1. run方法只是Runnable接口的一个普通方法可以执行多次，需要调用类重写此方法，执行此方法就是执行业务
2. start方法是Thread类的线程安全的启动方法，只能执行一次

public synchronized void start() {
        /**
         * This method is not invoked for the main method thread or "system"
         * group threads created/set up by the VM. Any new functionality added
         * to this method in the future may have to also be added to the VM.
         *
         * A zero status value corresponds to state "NEW".
         */
        if (threadStatus != 0)
            throw new IllegalThreadStateException();

        /* Notify the group that this thread is about to be started
         * so that it can be added to the group's list of threads
         * and the group's unstarted count can be decremented. */
        group.add(this);

        boolean started = false;
        try {
            start0();
            started = true;
        } finally {
            try {
                if (!started) {
                    group.threadStartFailed(this);
                }
            } catch (Throwable ignore) {
                /* do nothing. If start0 threw a Throwable then
                  it will be passed up the call stack */
            }
        }
    }

线程的优先级

/**
  * The minimum priority that a thread can have.
  */
 public final static int MIN_PRIORITY = 1;

/**
  * The default priority that is assigned to a thread.
  */
 public final static int NORM_PRIORITY = 5;

 /**
  * The maximum priority that a thread can have.
  */
 public final static int MAX_PRIORITY = 10;

明日计划 idea导入mybatis源码开始源码之旅。。。