BuiltIns.java
/*
** Module : BuiltIns.java
** Abstract : Helper class to simplify access to built-in functions
**
** Copyright (c) 2004-2017, Golden Code Development Corporation.
**
** -#- -I- --Date-- --JPRM-- ----------------------------Description------------------------------
** 001 ECF 20080312 @37510 Created initial version. Helper class to
** simplify access to built-in functions.
** 002 CA 20130408 Ensure the public and support functions are always sorted by name
** (as Class.getDeclaredMethods returns them in an undetermined order).
** 003 CA 20190722 Do not register a method without a HQLFunction annotation.
*/
/*
** This program is free software: you can redistribute it and/or modify
** it under the terms of the GNU Affero General Public License as
** published by the Free Software Foundation, either version 3 of the
** License, or (at your option) any later version.
**
** This program 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 Affero General Public License for more details.
**
** You may find a copy of the GNU Affero GPL version 3 at the following
** location: https://www.gnu.org/licenses/agpl-3.0.en.html
**
** Additional terms under GNU Affero GPL version 3 section 7:
**
** Under Section 7 of the GNU Affero GPL version 3, the following additional
** terms apply to the works covered under the License. These additional terms
** are non-permissive additional terms allowed under Section 7 of the GNU
** Affero GPL version 3 and may not be removed by you.
**
** 0. Attribution Requirement.
**
** You must preserve all legal notices or author attributions in the covered
** work or Appropriate Legal Notices displayed by works containing the covered
** work. You may not remove from the covered work any author or developer
** credit already included within the covered work.
**
** 1. No License To Use Trademarks.
**
** This license does not grant any license or rights to use the trademarks
** Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
** of Golden Code Development Corporation. You are not authorized to use the
** name Golden Code, FWD, or the names of any author or contributor, for
** publicity purposes without written authorization.
**
** 2. No Misrepresentation of Affiliation.
**
** You may not represent yourself as Golden Code Development Corporation or FWD.
**
** You may not represent yourself for publicity purposes as associated with
** Golden Code Development Corporation, FWD, or any author or contributor to
** the covered work, without written authorization.
**
** 3. No Misrepresentation of Source or Origin.
**
** You may not represent the covered work as solely your work. All modified
** versions of the covered work must be marked in a reasonable way to make it
** clear that the modified work is not originating from Golden Code Development
** Corporation or FWD. All modified versions must contain the notices of
** attribution required in this license.
*/
package com.goldencode.p2j.persist.pl;
import java.lang.reflect.*;
import java.util.*;
/**
* Helper class to simplify access to built-in function backing methods.
* Exposes all standard methods which need to run within the database.
*/
public final class BuiltIns
{
/** Classes which contain backing methods of public built-in functions */
private static final Class<?>[] publicFunctionClasses = new Class<?>[]
{
Functions.class,
Operators.class,
};
/** Classes which contain backing methods of support functions */
private static final Class<?>[] supportFunctionClasses = new Class<?>[]
{
ErrorHandler.class,
};
/**
* Private constructor. All access is via static methods.
*/
private BuiltIns()
{
}
/**
* Get a list of all public built-in and support function backing methods.
*
* @return List of backing methods for all functions.
*/
public static List<Method> getStandardFunctions()
{
ArrayList<Method> list = new ArrayList<Method>();
list.addAll(getPublicFunctions());
list.addAll(getSupportFunctions());
list.trimToSize();
return list;
}
/**
* Get a list of all public built-in function backing methods.
*
* @return List of backing methods for built-in functions.
*/
public static List<Method> getPublicFunctions()
{
return getMethodList(publicFunctionClasses);
}
/**
* Get a list of all support function backing methods.
*
* @return List of backing methods for support functions.
*/
public static List<Method> getSupportFunctions()
{
return getMethodList(supportFunctionClasses);
}
/**
* Given an array of classes, extract all public, static methods and
* return them in a list.
*
* @param classes
* Classes from which to extract methods.
*
* @return List of all public, static methods.
*/
private static List<Method> getMethodList(Class<?>[] classes)
{
ArrayList<Method> list = new ArrayList<Method>();
for (Class<?> clazz : classes)
{
list.addAll(getMethodList(clazz));
}
list.trimToSize();
// sort the methods by their full signature
Collections.sort(list, new Comparator<Method>()
{
public int compare(Method m1, Method m2)
{
return m1.toString().compareTo(m2.toString());
}
});
return Collections.unmodifiableList(list);
}
/**
* Given a single class, extract all public, static methods and return them
* in a list.
*
* @param clazz
* Class from which to extract methods.
*
* @return List of all public, static methods.
*/
private static List<Method> getMethodList(Class<?> clazz)
{
List<Method> list = new ArrayList<Method>();
Method[] all = clazz.getDeclaredMethods();
for (Method method : all)
{
int mod = method.getModifiers();
if (Modifier.isPublic(mod) &&
Modifier.isStatic(mod) &&
method.isAnnotationPresent(HQLFunction.class))
{
list.add(method);
}
}
return list;
}
}