reflectionhelper.java

Java的面向对象数据库系统的源代码

package org.ozoneDB.core.helper;

import org.ozoneDB.core.MethodKey;

import java.lang.reflect.Method;
import java.util.Set;
import java.util.Iterator;
import java.util.TreeSet;

/**
 * Created by IntelliJ IDEA.
 * User: administrator
 * Date: 2003-sep-13
 * Time: 20:18:05
 * To change this template use Options | File Templates.
 */
public class ReflectionHelper
{
  public final static String SIGNATURE_DELIMITER ="|";

  public static String signature(Class[] args) {
      String result = new String();
      for (int i = 0; i < args.length; i++) {
          result = i > 0 ? result + SIGNATURE_DELIMITER : result;
          result = result + args[i].getName();
      }
      return "\"" + result + "\"";
  }

  public static String signature(String[] args) {
      String result = new String();
      for (int i = 0; i < args.length; i++) {
          result = i > 0 ? result + SIGNATURE_DELIMITER : result;
          result = result + args[i];
      }
      return "\"" + result + "\"";
  }

  /**
   * Returns the array index of the specified method within the array
   * of methods of this class.
   */
  public static int methodArrayIndex(Method[] methods, Method m) {
      String mName = m.getName();
      String mSig = ReflectionHelper.signature(m.getParameterTypes());

      for (int i = 0; i < methods.length; i++) {
          String cName = methods[i].getName();
          String cSig = ReflectionHelper.signature(methods[i].getParameterTypes());
          if (mName.equals(cName) && mSig.equals(cSig)) {
              return i;
          }
      }
      throw new RuntimeException(m + ": Unable to find method in class.");
  }

  public static Method[] methodsOfClass(Class cl) {
        //System.out.println("Methods of class: "+cl);
        Method[] methods = cl.getMethods();

        Set set = new TreeSet();

        for (int i = 0; i < methods.length; i++) {
            String name = methods[i].getName();
            String sig = ReflectionHelper.signature(methods[i].getParameterTypes());
            set.add(new MethodKey(cl.getName(), name, sig, methods[i]));
        }

        Iterator it = set.iterator();
        for (int i = 0; it.hasNext(); i++) {
            MethodKey key = (MethodKey) it.next();
            methods[i] = key.method();
        }
        return methods;
    }
}