Java多线程实战

来源：互联网发布：中国纺织品出口数据编辑：程序博客网时间：2024/06/03 23:05

实习的时候发现多线程方面知识比较薄弱，这段时间在学习汪文君老师的《Java高并发编程实战》，并做一些学习笔记，供以后复习。

我们在单线程情况下执行两个方法，默认是按照顺序执行的，如下面的读写数据库操作：

public class TryConcurrency1 {    public static void main(String[] args) {        readFromDataBase();        writeDataToFile();    }    private static void readFromDataBase() {        //read data from database and handle it.        try {            println("Test1:"+"Begin read data from db.");            Thread.sleep(1000 * 3L);            println("Test1:"+"Read data done and start handle it.");        } catch (InterruptedException e) {            e.printStackTrace();        }        println("Test1:"+"The data handle finish and successfully.");    }    private static void writeDataToFile() {        try {            println("Test2:"+"Begin write data to file.");            Thread.sleep(1000 * 10L);            println("Test2:"+"Write data done and start handle it.");        } catch (InterruptedException e) {            e.printStackTrace();        }        println("Test2:"+"The data handle finish and successfully.");    }    private static void println(String message) {        System.out.println(message);    }}

输出结果为：

如果我们要并行的读写数据库，那么我们就要用到多线程操作，如：

public class TryConcurrency1 {    public static void main(String[] args) {       Thread t=new Thread("read-Thread"){           @Override           public void run() {               println(Thread.currentThread().getName());//main               readFromDataBase();           }       };       t.start();       //通过匿名内部类的方式        new Thread("write-Thread"){            @Override            public void run() {                writeDataToFile();            }        }.start();    }    private static void readFromDataBase() {        //read data from database and handle it.        try {            println("Test1:"+"Begin read data from db.");            Thread.sleep(1000 * 3L);            println("Test1:"+"Read data done and start handle it.");        } catch (InterruptedException e) {            e.printStackTrace();        }        println("Test1:"+"The data handle finish and successfully.");    }    private static void writeDataToFile() {        try {            println("Test2:"+"Begin write data to file.");            Thread.sleep(1000 * 10L);            println("Test2:"+"Write data done and start handle it.");        } catch (InterruptedException e) {            e.printStackTrace();        }        println("Test2:"+"The data handle finish and successfully.");    }    private static void println(String message) {        System.out.println(message);    }}

值得注意的是：创建Thread并非一个线程，只有当启动之后才会成为一个线程。

阅读全文

0 0