package reflection;

 import java.lang.reflect.*;

 import java.util.*;

 public class ReflectionTest {

     public static void main(String[] args)

     {

         String name;

         if(args.length>0) name =args[0];

         else

         {

             Scanner in = new Scanner(System.in);

             System.out.println("Enter class name (e.g. java.util.Date):");

             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 " + name);

             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();

         }

         System.exit(0);

     }

     public static void printConstructors(Class cl)

     {

         Constructor[] constructors = cl.getDeclaredConstructors();

         for(Constructor c:constructors)

         {

             String name = c.getName();

             System.out.print("   ");

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

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

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

             Class[] paramTypes = c.getParameterTypes();

             for (int j=0; j<paramTypes.length; j++)

             {

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

                 System.out.print(paramTypes[j].getName());

             }

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

         }

     }

     public static void printMethods(Class cl)

     {

         Method[] methods = cl.getDeclaredMethods();

         for(Method m:methods)

         {

             Class retType = m.getReturnType();

             String name  = m.getName();

             System.out.print("   ");

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

             if(modifiers.length()>0) System.out.print(modifiers+" ");//private static final都是修饰符

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

             Class[] paramTypes = m.getParameterTypes();//获取一个方法的所有参数

             for(int j=0;j<paramTypes.length;j++)

             {

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

                 System.out.print(paramTypes[j].getName());//获取一个参数的类型

             }

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

         }

     }

     public static void printFields(Class cl)

     {

         Field[] fields = cl.getDeclaredFields();

         for(Field f:fields)

         {

             Class type = f.getType();

             String name = f.getName();

             System.out.print("   ");

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

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

             System.out.println(type.getName()+" "+ name +";");

         }

     }

 }