Merge branch 'master' of https://github.com/xiongraorao/Interview-Notebook

code/src/main/java/com/raorao/Test.java

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+package com.raorao;
+
+/**
+ * .
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-02-16:46
+ */
+public class Test {
+
+  private int a;
+
+  public static void main(String[] args) {
+    //System.out.println(foo());
+    int r = new Test().foo();
+    System.out.println(r);
+  }
+
+  public int foo() {
+    try {
+      System.out.println("sadfasdfasdf");
+      return a;
+    } catch (Exception e) {
+      e.printStackTrace();
+      return 3;
+    } finally {
+      System.out.println("finally: " + ++a);
+      return a;
+    }
+  }
+}

code/src/main/java/com/raorao/java/base/InnerClassTest.java

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+package com.raorao.java.base;
+
+/**
+ * 内部类的引用.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-06-14:43
+ */
+public class InnerClassTest {
+  void f(){
+    System.out.println("InnerClassTest.f()");
+  }
+  public class Inner{
+    public InnerClassTest outer(){
+      return InnerClassTest.this;
+    }
+  }
+
+  public Inner inner(){
+    return new Inner();
+  }
+
+  public static void main(String[] args) {
+    InnerClassTest test = new InnerClassTest();
+    InnerClassTest.Inner inner = test.new Inner();
+    //inner = new InnerClassTest.Inner(); // 如果Inner 是static就可以，否则只能采用上面的语句
+  }
+}

code/src/main/java/com/raorao/java/thread/ReentrantLockTest.java

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+package com.raorao.java.thread;
+
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * 可重入锁测试.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-06-10:27
+ */
+public class ReentrantLockTest {
+
+  private Lock lock = new ReentrantLock();
+  private Condition conditionA = lock.newCondition();
+  private Condition conditionB = lock.newCondition();
+
+  public static void main(String[] args) throws InterruptedException {
+    ReentrantLockTest test = new ReentrantLockTest();
+    new Thread(() -> test.testLock()).start();
+    new Thread(() -> test.testLock()).start();
+
+    Thread t = new Thread(() -> test.awaitA());
+    t.start();
+    Thread.sleep(2000);
+    test.signalA();
+
+  }
+
+  public void awaitA() {
+    lock.lock();
+    try {
+      System.out.println("before awaitA at " + System.currentTimeMillis());
+      conditionA.await(); // 在此之前必须获得锁，不然报错illegalMonitorStateException 错误
+      System.out.println("after awaitA at " + System.currentTimeMillis());
+    } catch (InterruptedException e) {
+      e.printStackTrace();
+    } finally {
+      lock.unlock();
+      System.out.println(" 释放锁 awaitA ");
+    }
+  }
+
+  public void signalA() {
+    lock.lock();
+    try {
+      System.out.println("signalA at " + System.currentTimeMillis());
+      conditionA.signal(); // 在此之前必须获得锁，不然报错illegalMonitorStateException 错误
+      System.out.println("signalA over at " + System.currentTimeMillis());
+    } finally {
+      lock.unlock();
+      System.out.println(" 释放锁 signalA ");
+    }
+  }
+
+  public void testLock() {
+    lock.lock();
+    for (int i = 0; i < 5; i++) {
+      System.out.print(i + " ");
+    }
+    System.out.println();
+    lock.unlock();
+  }
+}

code/src/main/java/com/raorao/java/thread/ReentrantReadWriteLockTest.java

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+package com.raorao.java.thread;
+
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+/**
+ * 读写锁测试.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-06-11:48
+ */
+public class ReentrantReadWriteLockTest {
+
+  private ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
+
+  public void read(){
+    lock.readLock().lock(); // 读锁
+    System.out.println("获得读锁 " + Thread.currentThread().getName() + " " + System.currentTimeMillis());
+    try {
+      Thread.sleep(2000);
+    } catch (InterruptedException e) {
+      e.printStackTrace();
+    }finally {
+      lock.readLock().unlock();
+    }
+  }
+
+  public void write(){
+    lock.writeLock().lock(); // 写锁
+    System.out.println("获得写锁 " + Thread.currentThread().getName() + " " + System.currentTimeMillis());
+    try {
+      Thread.sleep(2000);
+    } catch (InterruptedException e) {
+      e.printStackTrace();
+    }finally {
+      lock.writeLock().unlock();
+    }
+  }
+
+  public static void main(String[] args) {
+    // 1. 读读共享, A 和 B 同时获得锁
+    ReentrantReadWriteLockTest test = new ReentrantReadWriteLockTest();
+    Thread t1 = new Thread(()-> {
+      Thread.currentThread().setName("A");
+      test.read();
+    });
+    Thread t2 = new Thread(()-> {
+      Thread.currentThread().setName("B");
+      test.read();
+    });
+    t1.start();
+    t2.start();
+
+    // 2. 写写互斥, D线程比C线程落后两秒执行
+    t1 = new Thread(()->{
+      Thread.currentThread().setName("C");
+      test.write();
+    });
+    t2 = new Thread(()->{
+      Thread.currentThread().setName("D");
+      test.write();
+    });
+    t1.start();
+    t2.start();
+
+  }
+
+
+}

code/src/main/java/com/raorao/java/thread/ThreadLocalTest.java

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+/*
+ * Copyright (c) 2018.  Xiong Raorao. All rights reserved.
+ * Project Name: book-notes
+ * File Name: Test.java
+ * Date: 18-7-25 下午5:32
+ * Author: Xiong Raorao
+ */
+
+package com.raorao.java.thread;
+
+/**
+ * .
+ *
+ * @author Xiong Raorao
+ * @since 2018-07-25-17:32
+ */
+public class ThreadLocalTest {
+  private static ThreadLocal<Integer> local = new ThreadLocal<>();
+  public static void main(String[] args) throws InterruptedException {
+    Thread t1 = new Thread(() -> {
+      System.out.println(" I am t1");
+      local.set(1);
+      try {
+        Thread.sleep(2000);
+        System.out.println("t1 value: "  + local.get());
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    });
+    Thread.sleep(2000);
+    Thread t2 = new Thread(() -> {
+      System.out.println("I am t2");
+      System.out.println("before set , I get " + local.get());
+      try {
+        Thread.sleep(2000);
+        local.set(2);
+        System.out.println("set after 2 s, I get " + local.get());
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    });
+    t2.start();
+    t1.start();// 无论怎么更换两个线程的启动顺序，得到的值是不一样的
+  }
+}

code/src/main/java/com/raorao/java/thread/TimerTest.java

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+package com.raorao.java.thread;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Timer;
+import java.util.TimerTask;
+
+/**
+ * 定时器.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-06-13:07
+ */
+public class TimerTest {
+  private static Timer timer = new Timer();
+
+  static class MyTask extends TimerTask{
+
+    @Override
+    public void run() {
+      System.out.println("运行时间： " + new Date());
+    }
+  }
+
+  public static void main(String[] args) {
+    MyTask task1 = new MyTask();
+    try {
+      Date taskDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse("2018-08-06 13:15:00");
+      System.out.println("执行时间： " + taskDate.toLocaleString() + "，当前时间" + new Date().toLocaleString());
+      timer.schedule(task1, taskDate);
+    } catch (ParseException e) {
+      e.printStackTrace();
+    }
+  }
+}