1 package reflection;
2
3 import java.lang.reflect.*;
4 import java.util.*;
5
6 public class ReflectionTest {
7 public static void main(String[] args)
8 {
9 String name;
10 if(args.length>0) name =args[0];
11 else
12 {
13 Scanner in = new Scanner(System.in);
14 System.out.println("Enter class name (e.g. java.util.Date):");
15 name = in.next();
16 }
17 try
18 {
19 Class cl = Class.forName(name);
20 Class supercl = cl.getSuperclass();
21 String modifiers = Modifier.toString(cl.getModifiers());
22 if (modifiers.length() > 0) System.out.print(modifiers + " ");
23 System.out.print("class " + name);
24 if (supercl != null && supercl != Object.class) System.out.print(" extends " + supercl.getName());
25
26 System.out.print("\n{\n");
27 printConstructors(cl);
28 System.out.println();
29 printMethods(cl);
30 System.out.println();
31 printFields(cl);
32 System.out.println("}");
33
34 }
35 catch (ClassNotFoundException e)
36 {
37 e.printStackTrace();
38 }
39 System.exit(0);
40 }
41 public static void printConstructors(Class cl)
42 {
43 Constructor[] constructors = cl.getDeclaredConstructors();
44 for(Constructor c:constructors)
45 {
46 String name = c.getName();
47 System.out.print(" ");
48 String modifiers = Modifier.toString(c.getModifiers());
49 if(modifiers.length()>0) System.out.print(modifiers+" ");
50 System.out.print(name+"(");
51
52 Class[] paramTypes = c.getParameterTypes();
53 for (int j=0; j<paramTypes.length; j++)
54 {
55 if(j>0) System.out.print(", ");
56 System.out.print(paramTypes[j].getName());
57 }
58 System.out.println(");");
59 }
60 }
61
62 public static void printMethods(Class cl)
63 {
64 Method[] methods = cl.getDeclaredMethods();
65
66 for(Method m:methods)
67 {
68 Class retType = m.getReturnType();
69 String name = m.getName();
70
71 System.out.print(" ");
72 String modifiers = Modifier.toString(m.getModifiers());
73 if(modifiers.length()>0) System.out.print(modifiers+" ");//private static final都是修饰符
74 System.out.print(retType.getName()+" "+name + "(");
75
76 Class[] paramTypes = m.getParameterTypes();//获取一个方法的所有参数
77 for(int j=0;j<paramTypes.length;j++)
78 {
79 if(j>0) System.out.print(", ");
80 System.out.print(paramTypes[j].getName());//获取一个参数的类型
81 }
82 System.out.println(");");
83 }
84 }
85
86 public static void printFields(Class cl)
87 {
88 Field[] fields = cl.getDeclaredFields();
89
90 for(Field f:fields)
91 {
92 Class type = f.getType();
93 String name = f.getName();
94 System.out.print(" ");
95 String modifiers = Modifier.toString(f.getModifiers());
96 if(modifiers.length()>0) System.out.print(modifiers+" ");
97 System.out.println(type.getName()+" "+ name +";");
98
99 }
100 }
101
102 }
