/* gnu.java.lang.ClassHelper
   Copyright (C) 1998 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */


package gnu.java.lang;

import java.util.*;
import java.lang.reflect.*;

/**
 ** ClassHelper has various methods that ought to have been
 ** in class.
 **
 ** @author John Keiser
 ** @version 1.1.0, 29 Jul 1998
 **/

public class ClassHelper {
	/** Strip the package part from the class name.
	 ** @param clazz the class to get the truncated name from
	 ** @return the truncated class name.
	 **/
	public static String getTruncatedClassName(Class clazz) {
		return getTruncatedName(clazz.getName());
	}
	/** Strip the package part from the class name, or the
	 ** class part from the method or field name.
	 ** @param name the name to truncate.
	 ** @return the truncated name.
	 **/
	public static String getTruncatedName(String name) {
		int lastInd = name.lastIndexOf('.');
		if(lastInd == -1) {
			return name;
		} else {
			return name.substring(lastInd+1);
		}
	}

	/** Strip the last portion of the name (after the last
	 ** dot).
	 ** @param name the name to get package of.
	 ** @return the package name.  "" if no package.
	 **/
	public static String getPackagePortion(String name) {
		int lastInd = name.lastIndexOf('.');
		if(lastInd == -1) {
			return "";
		} else {
			return name.substring(0,lastInd);
		}
	}

	static Hashtable allMethods = new Hashtable();
	static Hashtable allMethodsAtDeclaration = new Hashtable();

	/** Get all the methods, public, private and
	 ** otherwise, from the class, getting them
	 ** from the most recent class to find them.
	 **/
	public static Method[] getAllMethods(Class clazz) {
		Method[] retval = (Method[])allMethods.get(clazz);
		if(retval == null) {
			Method[] superMethods;
			if(clazz.getSuperclass() != null) {
				superMethods = getAllMethods(clazz.getSuperclass());
			} else {
				superMethods = new Method[0];
			}
			Vector v = new Vector();
			Method[] currentMethods = clazz.getDeclaredMethods();
			for(int i=0;i<currentMethods.length;i++) {
				v.addElement(currentMethods[i]);
			}
			for(int i=0;i<superMethods.length;i++) {
				boolean addOK = true;
				for(int j=0;j<currentMethods.length;j++) {
					if(getTruncatedName(superMethods[i].getName()).equals(getTruncatedName(currentMethods[j].getName()))
					   && ArrayHelper.equalsArray(superMethods[i].getParameterTypes(),currentMethods[j].getParameterTypes())) {
						addOK = false;
					}
				}
				if(addOK) {
					v.addElement(superMethods[i]);
				}
			}

			retval = new Method[v.size()];
			v.copyInto(retval);
			allMethods.put(clazz,retval);
		}
		return retval;
	}

	/** Get all the methods, public, private and
	 ** otherwise, from the class, and get them from
	 ** their point of declaration.
	 **/
	public static Method[] getAllMethodsAtDeclaration(Class clazz) {
		Method[] retval = (Method[])allMethodsAtDeclaration.get(clazz);
		if(retval == null) {
			Method[] superMethods;
			if(clazz.getSuperclass() != null) {
				superMethods = getAllMethodsAtDeclaration(clazz.getSuperclass());
			} else {
				superMethods = new Method[0];
			}
			Vector v = new Vector();
			Method[] currentMethods = clazz.getDeclaredMethods();
			for(int i=0;i<superMethods.length;i++) {
				v.addElement(superMethods[i]);
			}
			for(int i=0;i<superMethods.length;i++) {
				boolean addOK = true;
				for(int j=0;j<currentMethods.length;j++) {
					if(getTruncatedName(superMethods[i].getName()).equals(getTruncatedName(currentMethods[j].getName()))
					   && ArrayHelper.equalsArray(superMethods[i].getParameterTypes(),currentMethods[j].getParameterTypes())) {
						addOK = false;
					}
				}
				if(addOK) {
					v.addElement(superMethods[i]);
				}
			}

			retval = new Method[v.size()];
			v.copyInto(retval);
			allMethodsAtDeclaration.put(clazz,retval);
		}
		return retval;
	}

	static Hashtable allFields = new Hashtable();
	static Hashtable allFieldsAtDeclaration = new Hashtable();

	/** Get all the fields, public, private and
	 ** otherwise, from the class, getting them
	 ** from the most recent class to find them.
	 **/
	public static Field[] getAllFields(Class clazz) {
		Field[] retval = (Field[])allFields.get(clazz);
		if(retval == null) {
			Field[] superFields;
			if(clazz.getSuperclass() != null) {
				superFields = getAllFields(clazz.getSuperclass());
			} else {
				superFields = new Field[0];
			}
			Vector v = new Vector();
			Field[] currentFields = clazz.getDeclaredFields();
			for(int i=0;i<currentFields.length;i++) {
				v.addElement(currentFields[i]);
			}
			for(int i=0;i<superFields.length;i++) {
				boolean addOK = true;
				for(int j=0;j<currentFields.length;j++) {
					if(getTruncatedName(superFields[i].getName()).equals(getTruncatedName(currentFields[j].getName()))) {
						addOK = false;
					}
				}
				if(addOK) {
					v.addElement(superFields[i]);
				}
			}

			retval = new Field[v.size()];
			v.copyInto(retval);
			allFields.put(clazz,retval);
		}
		return retval;
	}

	/** Get all the fields, public, private and
	 ** otherwise, from the class, and get them from
	 ** their point of declaration.
	 **/
	public static Field[] getAllFieldsAtDeclaration(Class clazz) {
		Field[] retval = (Field[])allFieldsAtDeclaration.get(clazz);
		if(retval == null) {
			Field[] superFields;
			if(clazz.getSuperclass() != null) {
				superFields = getAllFieldsAtDeclaration(clazz.getSuperclass());
			} else {
				superFields = new Field[0];
			}
			Vector v = new Vector();
			Field[] currentFields = clazz.getDeclaredFields();
			for(int i=0;i<superFields.length;i++) {
				v.addElement(superFields[i]);
			}
			for(int i=0;i<superFields.length;i++) {
				boolean addOK = true;
				for(int j=0;j<currentFields.length;j++) {
					if(getTruncatedName(superFields[i].getName()).equals(getTruncatedName(currentFields[j].getName()))) {
						addOK = false;
					}
				}
				if(addOK) {
					v.addElement(superFields[i]);
				}
			}

			retval = new Field[v.size()];
			v.copyInto(retval);
			allFieldsAtDeclaration.put(clazz,retval);
		}
		return retval;
	}
}
