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import java.lang.reflect.*;import java.util.Map;public class Test {	public String name = null;	private int cnt = 1;		public void setCnt(int cnt)	{		this.cnt = cnt;	}		public Test()	{			}		public Test(String name)	{		this.name = name;	}		public void test()	{		Method[] method = Test.class.getMethods();		for( Method item:method )		{			System.out.println("Method in test: "+item.getName());		}				/*Get fields*/		Field[] fields = Test.class.getFields();		for( Field field:fields )		{			System.out.println("field name ="+field.getName()); /*Only private fields can be accessed*/		}				/*Modify field value*/		try		{			Field namefield = Test.class.getField("name");						Test newtest = new Test();			newtest.name = new String("hahaha");						String value = (String)namefield.get(newtest); /*Use the Field object to get value of this field belongs to the specific object*/			System.out.println("value ="+value);						/*Now modify the field*/			value = new String("heiheihei");			namefield.set(newtest, value);			System.out.println("new value="+newtest.name);		}		catch(Exception e)		{			e.printStackTrace();		}				/*Get all constructors*/		Constructor
   [] constructors = Test.class.getConstructors();		for( Constructor cons:constructors )		{			System.out.println("Constructor name="+cons.getName());		}				/*Get the constructor that takes a String as argument*/		try		{			/*usr constructor to instantiate an object*/			Constructor cons = Test.class.getConstructor(String.class);						Test test1 = (Test)cons.newInstance("CreatedViaConstructorClass");			System.out.println("Name = "+test1.name);					/*Get class name*/				System.out.println("modifiers: "+ Test.class.getModifiers());			System.out.println("name: "+Map.class.getName());			System.out.println("simple-name: "+Map.class.getSimpleName());			System.out.println("");						/*Get method,use the method object to invoke the method*/			Method methodlocal = Test.class.getMethod("test", null);			Test test2 = new Test();			System.out.println("++++++++++\r\n");			//Object returnvalue = methodlocal.invoke(test2, null);								/*@Get privite field*/			Field fieldint = Test.class.getDeclaredField("cnt"); /*getField can only get public fields*/			fieldint.setAccessible(true);						Test test3 = new Test();			test3.setCnt(12);						int cntvalue = fieldint.getInt(test3);			System.out.println("private field cnt ="+cntvalue);		}		catch(Exception e)		{			e.printStackTrace();		}	}		public String classname()	{		return Test.class.getSimpleName();	}}

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