java - 如何列出不被继承的方法?

标签 java reflection

我有以下两个 Java 类(Command 和 Player)。我希望能够从 Command 类中列出 Player 类中的所有公共(public)方法,而不必对它们进行硬编码。我尝试了多种方法,包括接口(interface)或命令模式,但我对 Java 不熟悉,无法使它们工作。

在我看来,使用Java的反射API会更容易。但是,当我使用它从 Player 类打印公共(public)方法时,我得到了无关的方法,我认为这些方法是从 Object 类继承的。

有没有办法只包含我自己定义的那些方法(即以“public method: public void Player.”开头的方法)?

谢谢,

液相色谱

这是我得到的输出:

public method: public void Player.search(Command)
public method: public Room Player.getCurrentRoom()
public method: public void Player.engage()
public method: public void Player.trade(Command)
public method: public void Player.goRoom(Command)
public method: public void Player.takeItem(Command)
public method: public void Player.dropItem(Command)
public method: public void Player.lock(Command)
public method: public void Player.unlock(Command)
public method: public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException
public method: public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException
public method: public final void java.lang.Object.wait() throws java.lang.InterruptedException
public method: public boolean java.lang.Object.equals(java.lang.Object)
public method: public java.lang.String java.lang.Object.toString()
public method: public native int java.lang.Object.hashCode()
public method: public final native java.lang.Class java.lang.Object.getClass()
public method: public final native void java.lang.Object.notify()
public method: public final native void java.lang.Object.notifyAll()

这是命令类:

import java.lang.reflect.Method;

public class Command
{

    // a constant array that holds all valid command words
    private static String[] validCommands;      

    private String commandWord;
    private String secondWord;

    public Command(String firstWord, String secondWord)
    {
        commandWord = firstWord;
        this.secondWord = secondWord;
    }

        [...] //some code omitted

    public boolean process(Player player) 
    {

        Class pClass = player.getClass();
        Method[] methods = pClass.getMethods();
        for (int i = 0; i < methods.length; i++) {
            System.out.println("public method: " + methods[i]);
        }

        boolean wantToQuit = false;

        if(commandWord == null) {
            System.out.println("I don't know what you mean...");
            return false;
        }

        if (commandWord.equals("help")) {
            printHelp();
        }
        else if (commandWord.equals("go")) {
            player.goRoom(this);
        }
        else if (commandWord.equals("quit")) {
            wantToQuit = quit();
        }
        else if (commandWord.equals("take")) {
            player.takeItem(this);
        }
        else if (commandWord.equals("drop")) {
            player.dropItem(this);
        }
        else if (commandWord.equals("search")) {
            player.search(this);
        }
        else if (commandWord.equals("engage")) {
            player.engage();
        }
        else if (commandWord.equals("trade")) {
            player.trade(this);
        }
        else if (commandWord.equals("lock")) {
            player.lock(this);
        }
        else if (commandWord.equals("unlock")) {
            player.unlock(this);
        }
        else {
            System.out.println("Invalid command. Type 'help' if you forgot the list of available commands.");
        }
        // else command not recognised.
        return wantToQuit;
    }
}

这是 Player 类的概要:

public class Player
{
    private String name;
    private Room currentRoom;
    private ArrayList<Item> items;

    Player (String name, Room startingRoom)
    {
        this.name = name;
        items = new ArrayList<Item>();
        this.currentRoom = startingRoom;
        printWelcome();
    }

    public void engage()
    {
        [...]
    }

    public void trade(Command command) 
    {
        [...]       }

    public void goRoom(Command command) 
    {   
        [...]       }

    public void search(Command command) 
    {
        [...]       }

    public void takeItem(Command command) 
    {
        [...]       }

    public void dropItem(Command command) 
    {
        [...]       }

    public void lock(Command command)
    {   
        [...]       }

    public void unlock(Command command)
    {   
        [...]
    }

}

最佳答案

您想要使用 Java 反射 API 中的 getDeclaredMethods() 类。

http://docs.oracle.com/javase/7/docs/api/java/lang/Class.html#getDeclaredMethods()

这只会为您提供在相关类上声明的方法,忽略父类(super class)和接口(interface)。

关于java - 如何列出不被继承的方法?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22799106/

相关文章:

java - 代号一 : Annotation Processing

java - Selenium implicitlyWait 不工作?

PHP 方法链 - 反射?

java - 在每个方法的开头检查 NullPointerException

java - JPQL - 带过滤器的 JOIN 查询

java - 线程 "AWT-EventQueue-1"中的异常

reflection - 在未知(任何)对象上调用kclass.memberProperties是否安全?

c++ - 在一系列成员变量上调用运算符

Java 在公共(public)抽象父类(super class)上反射非法访问异常

Java 8 是否有可能使用反射或其他方法在方法中插入代码?