java通過反射取得一個類的完整結構

首先我們在person包中新建一個Person.java：

package person;

import sex.Sex;

public class Person{
	private String name = null;
	private int age = 0;
	private Sex sex = null;
	private String birthday = null;
	
	public Person(){};
	public Person(String name, int age, Sex sex, String birthday){
		String birMatch = "\\d{4}-\\d{2}-\\d{2}";
		this.name = name;
		this.age = age;
		this.sex = sex;
		if(birthday.matches(birMatch)){
			this.birthday = birthday;
		}
	}
	public void setInfo(String name, int age, Sex sex, String birthday){
		String birMatch = "\\d{4}-\\d{2}-\\d{2}";
		this.name = name;
		this.age = age;
		this.sex = sex;
		if(birthday.matches(birMatch)){
			this.birthday = birthday;
		}
	}
	public String getPerName(){
		return this.name;
	}
	public int getAge(){
		return this.age;
	}
	public Sex getSex(){
		return this.sex;
	}
	public String getBirthday(){
		return this.birthday;
	}
	public String toString(){
		return this.name + ", " + this.age + " years old, " + this.sex + ", " + this.birthday;
	}
}

　　然后在sex包中建立一個枚舉Sex.java：

package sex;

public enum Sex{
	MALE, FEMALE;
}

　　再在main包的主方法取得Person類的完整結構：

package main;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;

import person.Person;
import sex.Sex;

public class Main {
	public static void main(String[] args){	
		try {
			Class<?> cls = Class.forName("person.Person");  //打開類
			Field[] var = cls.getDeclaredFields();   //取得類的屬性
			Constructor<?>[] consMeth = cls.getConstructors();   //取得類的所有構造函數
			Method[] meth = cls.getMethods();       //取得類的所有方法
			for(int i=0; i<var.length; i++){        //輸出屬性
				System.out.println(var[i].toGenericString());   
			}
			for(int i=0; i<consMeth.length; i++){     //輸出構造函數
				System.out.println(consMeth[i].toGenericString());
			}
			for(int i=0; i<meth.length; i++){          //輸出方法
				System.out.println(meth[i].toGenericString());
			}
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

　　運行結果：

private java.lang.String person.Person.name
private int person.Person.age
private sex.Sex person.Person.sex
private java.lang.String person.Person.birthday
public person.Person()
public person.Person(java.lang.String,int,sex.Sex,java.lang.String)
public java.lang.String person.Person.toString()
public sex.Sex person.Person.getSex()
public java.lang.String person.Person.getPerName()
public void person.Person.setInfo(java.lang.String,int,sex.Sex,java.lang.String)
public int person.Person.getAge()
public java.lang.String person.Person.getBirthday()
public final void java.lang.Object.wait() throws java.lang.InterruptedException
public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException
public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException
public boolean java.lang.Object.equals(java.lang.Object)
public native int java.lang.Object.hashCode()
public final native java.lang.Class<?> java.lang.Object.getClass()
public final native void java.lang.Object.notify()
public final native void java.lang.Object.notifyAll()

　　結果說明該類繼承得到的方法也可以得到。