各种反射的用法

[java]代码库

 import java.lang.reflect.Field;
 public class ReflectTest{
   public static void main(String[] args){
     String str1="abc";
     Class cls1=str1.getClass();
     Class cls2=String.class;
     //Class cls3=Class.forName("java.lang.String");
     System.out.println(cls1==cls2);
    // System.out.println(cls1==cls3);
      System.out.println(cls1.isPrimitive());
      System.out.println(int.class.isPrimitive());
      System.out.println(int.class==Integer.class);
      System.out.println(int.class==Integer.TYPE);
      System.out.println(int[].class.isPrimitive());
      try{
      //获取相对应的字段
      ReflectPoint pt1=new ReflectPoint(3,5);
      Field fieldY=pt1.getClass().getField("y");
      System.out.println(fieldY.get(pt1));
      Field fieldx=pt1.getClass().getDeclaredField("x");
      fieldx.setAccessible(true);
      System.out.println("a"+fieldx.get(pt1));
      changeStringValue(pt1);
      System.out.println(pt1);
      }catch(Exception e2)
      {
          System.out.println(e2);
      }
   }
 
     private static void changeStringValue(Object obj) throws Exception {
         Field[] fields=obj.getClass().getFields();
         for(Field field:fields){
             //field.getType().equals(String.class);
             if(field.getType()==String.class)
             {
                 //以后是取出相应的字段，然后用replace方法下替换字符
                 String oldValue=(String)field.get(obj);
                 String newValue=oldValue.replace('b', 'a');    
                 field.set(obj, newValue);
             }
         }
         
     }
 
 
 }