java反射

package v1ch02;

import java.lang.reflect.Constructor;

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

import java.util.Scanner;

public class ReflectionTest {

public static void main(String[] args) {

String name = null;

if (args.length > 0) {

name = args[0];

} else {

Scanner in = new Scanner(System.in);

name = in.next();

}

try {

Class cl = Class.forName(name);

Class supercl = cl.getSuperclass();

String modifiers = Modifier.toString(cl.getModifiers());

if (modifiers.length() > 0)

System.out.print(modifiers + " ");

System.out.print("class" + " " + cl.getName() + " ");

if (supercl != null && supercl != Object.class)

System.out.print("extends" + supercl.getName());

System.out.print("\n{\n");

printConstructors(cl);

System.out.println();

printMethods(cl);

System.out.println();

printFields(cl);

System.out.println("}");

} catch (ClassNotFoundException e) {

e.printStackTrace();

}

}

private static void printFields(Class cl) {

Field[] fields = cl.getFields();

for(Field f : fields){

System.out.print(" ");

String modifiers = Modifier.toString(f.getModifiers());

if(modifiers.length() > 0)System.out.print(modifiers+" ");

Class retType = f.getType();

System.out.println(retType.getName()+" "+f.getName()+";");

}

}

private static void printMethods(Class cl) {

Method[] methods = cl.getMethods();

for (Method m : methods) {

System.out.print(" ");

String modifiers = Modifier.toString(m.getModifiers());

if(modifiers.length() > 0)System.out.print(modifiers+" ");

Class retType = m.getReturnType();

System.out.print(retType.getName()+" ");

System.out.print(m.getName()+"(");

Class[] paramtersType = m.getParameterTypes();

for(int i = 0;i<paramtersType.length;i++){

if(i>0)System.out.print(",");

System.out.print(paramtersType[i].getName());

}

System.out.println(");");

}

}

private static void printConstructors(Class cl) {

Constructor[] constructors = cl.getConstructors();

for (Constructor c : constructors) {

System.out.print(" ");

String modifiers = Modifier.toString(c.getModifiers());

if (modifiers.length() > 0)

System.out.print(modifiers + " ");

System.out.print(c.getName());

Class[] parametersType = c.getParameterTypes();

for (int i = 0; i < parametersType.length; i++) {

if (i > 0)

System.out.print(",");

System.out.print(parametersType[i].getName());

}

System.out.println(");");

}

}

}