java获取Class类的信息

[java]代码库

package com.google.reflect;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.List;

public class AnalyticClassInfo
{

    private static String getModifier(int modifier)
    {
        String result = "";
        switch (modifier)
        {
        case Modifier.PRIVATE:
            result = "private";
            break;
        case Modifier.PUBLIC:
            result = "public";
            break;
        case Modifier.PROTECTED:
            result = "protected";
            break;
        case Modifier.ABSTRACT:
            result = "abstract";
            break;
        case Modifier.FINAL:
            result = "final";
            break;
        case Modifier.NATIVE:
            result = "native";
            break;
        case Modifier.STATIC:
            result = "static";
            break;
        case Modifier.SYNCHRONIZED:
            result = "synchronized";
            break;
        case Modifier.STRICT:
            result = "strict";
            break;
        case Modifier.TRANSIENT:
            result = "transient";
            break;
        case Modifier.VOLATILE:
            result = "volatile";
            break;
        case Modifier.INTERFACE:
            result = "interface";
            break;
        default:
            break;
        }
        return result;
    }

    private static void printClassDefinition(Class clz)
    {
        String clzModifier = getModifier(clz.getModifiers());
        if (clzModifier != null && !clzModifier.equals(""))
        {
            clzModifier += "  ";
        }

        String superClz = "";
        if(clz.getSuperclass()!=null)
        {
            superClz = clz.getSuperclass().getName();
            if (superClz != null && !superClz.equals(""))
            {
                superClz = " extends " + superClz;
            }
        }

        Class[] interfaces = clz.getInterfaces();
        String inters = "";
        for (int i = 0; i < interfaces.length; i++)
        {
            if (i == 0)
            {
                inters += " implements ";
            }
            inters += interfaces[i].getName();
        }

        System.out.println(clzModifier + clz.getName() + " " + superClz + " "
                + inters);

        System.out.println("{");

        System.out.println("fields:");
        Field[] fields = clz.getDeclaredFields();
        for (int i = 0; i < fields.length; i++)
        {
            String modifier = getModifier(fields[i].getModifiers());
            if (modifier != null && !modifier.equals(""))
            {
                modifier = modifier + " ";
            }
            String fieldName = fields[i].getName();
            String fieldType = fields[i].getType().getName();
            System.out.println("    " + modifier + fieldType + " " + fieldName
                    + ";");
        }

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

        Method[] methods = clz.getDeclaredMethods();
        for (int i = 0; i < methods.length; i++)
        {
            Method method = methods[i];

            String modifier = getModifier(method.getModifiers());
            if (modifier != null && !modifier.equals(""))
            {
                modifier = modifier + " ";
            }

            String methodName = method.getName();

            Class returnClz = method.getReturnType();
            String retrunType = returnClz.getName();

            Class[] clzs = method.getParameterTypes();
            String paraList = "(";
            for (int j = 0; j < clzs.length; j++)
            {
                paraList += clzs[j].getName();
                if (j != clzs.length - 1)
                {
                    paraList += ", ";
                }
            }
            paraList += ")";

            clzs = method.getExceptionTypes();
            String exceptions = "";
            for (int j = 0; j < clzs.length; j++)
            {
                if (j == 0)
                {
                    exceptions += "throws ";
                }

                exceptions += clzs[j].getName();

                if (j != clzs.length - 1)
                {
                    exceptions += ", ";
                }
            }

            exceptions += ";";

            String methodPrototype = modifier + retrunType + " " + methodName
                    + paraList + exceptions;

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

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

    /**
     * @param args
     */
    public static void main(String[] args)
    {
        // TODO Auto-generated method stub

//      printClassDefinition(List.class);
//      printClassDefinition(Proxy.class);
        printClassDefinition(ArrayList.class);
    }

}

//源代码片段来自云代码http://yuncode.net