反射技术总结

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import java.lang.reflect.*;
class most1{
	public static void main(String[] args)throws ClassNotFoundException{
		String s1="abc";
		Class c1=s1.getClass();
		Class c2=String.class;
		Class c3=Class.forName("java.lang.String");
		System.out.println(c1==c2);
		System.out.println(c1==c3);
		System.out.println(c1.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());
		System.out.println(int[].class.isArray());
	}
}

import java.lang.reflect.*;
class ReflectDemo{
	public static void main(String[] args)throws NoSuchMethodException,InstantiationException,IllegalAccessException,InvocationTargetException{
		Constructor tts=String.class.getConstructor(StringBuffer.class);
		String s1=(String)tts.newInstance(new StringBuffer("abc"));
		System.out.println(s1.charAt(2));
	}
}

import java.lang.reflect.*;
class ReflectPoint{
	public int x;
	private int y;
	ReflectPoint(int x,int y){
		this.x=x;
		this.y=y;
	}
}
class ReflectDemo{
	public static void main(String[] args)throws NoSuchFieldException,IllegalAccessException{
		ReflectPoint pt=new ReflectPoint(3,3);
		Field fieldX=pt.getClass().getField("x");
		System.out.println(fieldX.get(pt));
		Field fieldY=pt.getClass().getDeclaredField("y");
		fieldY.setAccessible(true);
		System.out.println(fieldX.get(pt));
	}
}

import java.lang.reflect.*;
class ReflectDemo{
	public static void main(String[] args)throws NoSuchMethodException,IllegalAccessException,InvocationTargetException{
		String s="abc";
		Class c1=s.getClass();
		Method method=String.class.getMethod("charAt",int.class);
		System.out.println(method.invoke(s,1));
		System.out.println(method.invoke(s,new Object[]{2}));
	}
}

import java.lang.reflect.*;
class ReflectPoint{
	String s1="abll";
	String s2="base";
	String s3="itcast";
	public String toString(){
		return s1+"--"+s2+"--"+s3;
	}
}
class ReflectDemo{
	public static void main(String[] args)throws IllegalAccessException{
		ReflectPoint pt=new ReflectPoint();
		Field[] fields=pt.getClass().getDeclaredFields();
		for(Field field:fields){
			if(field.getType()==String.class){
				String str=(String)field.get(pt);
				String value=str.replace('b','a');
				field.set(pt,value);
			}
		}
		System.out.println(pt);
	}
}

import java.lang.reflect.*;
class ReflectPoint{
	public static void main(String[] args)throws InvocationTargetException,ClassNotFoundException,NoSuchMethodException,IllegalAccessException{
		for(String str: args){
			System.out.println(str);
		}
	}
}
class ReflectDemo{
	public static void main(String[] args)throws InvocationTargetException,ClassNotFoundException,NoSuchMethodException,IllegalAccessException{
		String startName=args[0];
		Method mainMethod=Class.forName(startName).getMethod("main",String[].class);
		mainMethod.invoke(null,(Object)new String[]{"111","222","333"});
	}
}

import java.lang.reflect.*;
class ReflectDemo{
	public static void main(String[] args){
		String[] arr={"x","y","z"};
		printObject(arr);
		printObject("xyz");
	}
	public static void printObject(Object obj){
		Class c=obj.getClass();
		if(c.isArray()){
			int len=Array.getLength(obj);
			for(int x=0; x<len; x++){
				System.out.println(Array.get(obj,x));
			}
		}else{
			System.out.println(obj);
		}
	}
}

package pack;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
class ReflectPoint{
<span style="white-space: pre;">	</span>private int x;
<span style="white-space: pre;">	</span>private int y;
<span style="white-space: pre;">	</span>ReflectPoint(int x,int y){
<span style="white-space: pre;">		</span>this.x=x;
<span style="white-space: pre;">		</span>this.y=y;
<span style="white-space: pre;">	</span>}
<span style="white-space: pre;">	</span>public boolean equals(Object obj){
<span style="white-space: pre;">		</span>if(!(obj instanceof ReflectPoint))
<span style="white-space: pre;">			</span>throw new RuntimeException("类型不匹配");
<span style="white-space: pre;">		</span>ReflectPoint r=(ReflectPoint)obj;
<span style="white-space: pre;">		</span>return this.x==(r.x)&&this.y==r.y;
<span style="white-space: pre;">	</span>}
}
class ReflectDemo{
<span style="white-space: pre;">	</span>public static void main(String[] args){
<span style="white-space: pre;">		</span>Collection coll=new ArrayList();
<span style="white-space: pre;">		</span>ReflectPoint pt1=new ReflectPoint(3,3);
<span style="white-space: pre;">		</span>ReflectPoint pt2=new ReflectPoint(5,5);
<span style="white-space: pre;">		</span>ReflectPoint pt3=new ReflectPoint(3,3);
<span style="white-space: pre;">		</span>coll.add(pt1);
<span style="white-space: pre;">		</span>coll.add(pt2);
<span style="white-space: pre;">		</span>coll.add(pt3);
<span style="white-space: pre;">		</span>coll.add(pt1);
<span style="white-space: pre;">		</span>System.out.println(coll.size());
<span style="white-space: pre;">	</span>}
}

反射技术总结

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原文地址：http://blog.csdn.net/qiang3570/article/details/44489517