Ten years Hello World,actually writing is life

本文系投稿，作者：林杰。

作者寄语：十年hello world，写的是人生，每一段代码代表每一年和人生的过程。

欢迎点击阅读原文，跳转作者博客围观。

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//LinJie//Ten years Hello world，actually writing is life !//Original//First yearpublic class LinJie{ public static void main(String[] args) {   //hello world   System.out.println("hello world"); }}//Second yearspublic class LinJie{ public static void main(String[] args) {   //hello world   LinJie obj = new LinJie();   obj.toString(); } /* (non-Javadoc)  * @see java.lang.Object#toString()  */ @Override public String toString() {   return "hello world"; }}//The third yearpublic class LinJie{ private static LinJie instance; public static LinJie getInstance() {   if(instance == null)     instance = new LinJie();   return instance; } /* (non-Javadoc)  * @see java.lang.Object#toString()  */ @Override public String toString() {   return "hello world"; } public static void main(String[] args) {   //hello world   LinJie obj = LinJie.getInstance();   obj.toString(); }}//Fourth yearspublic class LinJie{ private final String a; //required private final String b; //required private final String c; //optional private final String d; //optional //Builder public static class Builder{   //required   private final String a;   private final String b;   //optional   private String c;   private String d;   public Builder(String a,String b) {     this.a = a;     this.b = b;   }   public Builder c(String val)     { c = val; return this; }   public Builder d(String val)     { d = val; return this; }   public LinJie build() {     return new LinJie(this);   } } private LinJie(Builder builder) {   a = builder.a;   b = builder.b;   c = builder.c;   d = builder.d; } /* (non-Javadoc)  * @see java.lang.Object#toString()  */ @Override public String toString() {   return c+" "+d; } public static void main(String[] args) {   //hello world   LinJie obj = new LinJie.Builder("lin", "jie").       c("hello").d("world").build();   System.out.println(obj.toString()); }}//Fifth years/*<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xsi:schemaLocation="       http://www.springframework.org/schema/beans       http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="linjie" class="com.linjie.LinJie"></bean></beans>*/public class LinJie{ @Test public void test() {   //hello world   ApplicationContext context = new ClassPathXmlApplicationContext               ("applicationContext.xml");   LinJie obj = (LinJie) context.getBean("linjie");   obj.hello_world(); } public void hello_world() {   System.out.println("hello world������֦,���һ��"); }}//Sixth years/*<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xmlns:aop="http://www.springframework.org/schema/aop"   xmlns:context="http://www.springframework.org/schema/context"   xsi:schemaLocation="http://www.springframework.org/schema/beans    http://www.springframework.org/schema/beans/spring-beans.xsd       http://www.springframework.org/schema/aop       http://www.springframework.org/schema/aop/spring-aop-4.0.xsd       http://www.springframework.org/schema/context       http://www.springframework.org/schema/context/spring-context-4.0.xsd">   <!-- 扫描 --> <context:component-scan base-package="com.linjie.aop">   </context:component-scan>  </beans>*/@Component("linjie")public class LinJie{ @Test public void test() {   //hello world   ApplicationContext context = new ClassPathXmlApplicationContext               ("applicationContext.xml");   LinJie obj = (LinJie) context.getBean("linjie");   obj.hello_world(); } public void hello_world() {   System.out.println("hello world"); }}//Seventh years/*<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xmlns:aop="http://www.springframework.org/schema/aop"   xmlns:context="http://www.springframework.org/schema/context"   xsi:schemaLocation="http://www.springframework.org/schema/beans    http://www.springframework.org/schema/beans/spring-beans.xsd    http://www.springframework.org/schema/aop    http://www.springframework.org/schema/aop/spring-aop-4.0.xsd    http://www.springframework.org/schema/context    http://www.springframework.org/schema/context/spring-context-4.0.xsd"> <context:component-scan base-package="com.linjie.aop">   </context:component-scan>   <aop:aspectj-autoproxy></aop:aspectj-autoproxy>  </beans>*//*@Component("arithmetic")public class Arithmetic { public void hello_world() {}}*/@Aspect@Component("linjie")public class LinJie{ @Test public void test() {   //hello world   ApplicationContext context = new ClassPathXmlApplicationContext               ("applicationContext.xml");   LinJie obj = (LinJie) context.getBean("linjie");   obj.hello_world(); } @Before("execution(* com.linjie.aop.Arithmetic.*(..))") public void Before_Loggin() {   System.out.println("hello world"); }}//Eighth years fail//Ninth years fail//Tenth yearspublic class LinJie { public static void main(String[] args) {   String grow       = "hello world";   String grow_up    = "hello world";   String grow_up_up = "hello world";   if(grow.equals(grow_up) && grow.equals(grow_up_up))     System.out.println(grow); }}