静态加载:
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package com.imooc.加载类; public class Office_Static { public static void main(String[] args) { //new 创建对象,是静态加载类,在编译时刻就需要加载所有的可能使用到的类 if ( "Word" .equals(args[ 0 ])){ Word w = new Word(); w.start(); } if ( "Excel" .equals(args[ 0 ])){ Excel e = new Excel(); e.start(); } } } |
这个程序编译时必须有Word和Excel这两个类存在才行,即使判断后用不到Excel也要加载
动态加载:
1、接口OfficeAble :
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package com.imooc.加载类; public interface OfficeAble { public void start(); } |
2、Word实现接口:
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package com.imooc.加载类; public class Word implements OfficeAble{ public void start(){ System.out.println( "word start" ); } } |
3、Excel实现接口:
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package com.imooc.加载类; public class Excel implements OfficeAble{ public void start(){ System.out.println( "excel start" ); } } |
4、Main方法
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package com.imooc.加载类; public class OfficeBetter { /** * @param args */ public static void main(String[] args) { try { //动态加载类,在运行时刻加载 Class c = Class.forName(args[ 0 ]); //在运行配置里面输入com.imooc.加载类.Excel //通过类类型,创建该类对象(先转换为Word和Excel的共同接口OfficeAble) OfficeAble oa = (OfficeAble)c.newInstance(); oa.start(); //不推荐下面两种,因为不确定是加载Word还是Excel,要强转 // Word word = (Word)c.newInstance(); // word.start(); // Excel excel = (Excel)c.newInstance(); // excel.start(); } catch (Exception e) { e.printStackTrace(); } } } |
以上就是小编为大家带来的Java反射之静态加载和动态加载的简单实例的全部内容了,希望对大家有所帮助,多多支持服务器之家~