/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source 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 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.config.types;
import com.caucho.config.ConfigException;
import com.caucho.el.EL;
import com.caucho.util.CharBuffer;
import com.caucho.util.L10N;
import javax.annotation.PostConstruct;
import javax.servlet.jsp.el.ELException;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
/**
* Constructor for a function signature.
*/
public class ResinType {
private final static L10N L = new L10N(ResinType.class);
private String _signature;
private String _className;
private ArrayList<String> _args = new ArrayList<String>();
private int _index;
/**
* Returns the signature.
*/
public String getSignature()
{
return _signature;
}
/**
* Returns the class name.
*/
public String getClassName()
{
return _className;
}
/**
* Adds the text value to the signature.
*/
public void addText(String value)
{
_signature = value;
}
/**
* Initialize the signature.
*/
@PostConstruct
public void init()
throws ConfigException
{
if (_signature == null)
throw new ConfigException(L.l("A Signature requires the method signature."));
parseSignature();
}
/**
* Creates the object.
*/
public Object create(Class targetClass)
throws ClassNotFoundException,
InstantiationException,
IllegalAccessException,
ConfigException,
InvocationTargetException,
ELException
{
ClassLoader loader = Thread.currentThread().getContextClassLoader();
Class cl = Class.forName(_className, false, loader);
if (targetClass != null && ! (targetClass.isAssignableFrom(cl)))
throw new ConfigException(L.l("{0} is not assignable to {1}",
targetClass.getName(), _className));
Constructor constructor = getConstructor(cl);
if (constructor == null)
throw new ConfigException(L.l("Can't find a matching public constructor for '{0}'",
_signature));
Object []args = new Object[_args.size()];
for (int i = 0; i < args.length; i++) {
String arg = _args.get(i);
args[i] = EL.evalObject(arg);
}
return constructor.newInstance(args);
}
private Constructor getConstructor(Class cl)
{
Constructor []cons = cl.getConstructors();
for (int i = 0; i < cons.length; i++) {
if (! Modifier.isPublic(cons[i].getModifiers()))
continue;
if (cons[i].getParameterTypes().length == _args.size())
return cons[i];
}
return null;
}
/**
* Parses the function signature.
*/
private void parseSignature()
throws ConfigException
{
_index = 0;
_className = parseType(skipWhitespace(read()));
CharBuffer cb = CharBuffer.allocate();
int ch = skipWhitespace(read());
if (ch < 0)
return;
if (ch != '(')
throw new ConfigException(L.l("constructor syntax is `className(arg1, ..., argn)' in `{0}'",
_signature));
ch = skipWhitespace(read());
while (ch > 0 && ch != ')') {
cb.clear();
while (ch > 0 && ch != ',' && ch != ')') {
cb.append((char) ch);
if (ch == '\'' || ch == '"') {
int end = ch;
for (ch = read(); ch > 0 && ch != end; ch = read()) {
cb.append((char) ch);
}
if (ch > 0)
cb.append((char) ch);
}
ch = read();
}
_args.add(cb.toString());
}
if (ch != ')')
throw new ConfigException(L.l("constructor syntax is `className(arg1, ..., argn)' in `{0}'",
_signature));
ch = skipWhitespace(read());
if (ch > 0)
throw new ConfigException(L.l("constructor syntax is `className(arg1, ..., argn)' in `{0}'",
_signature));
}
/**
* Parses the type.
*/
private String parseType(int ch)
throws ConfigException
{
CharBuffer cb = CharBuffer.allocate();
for (; Character.isJavaIdentifierPart((char) ch) || ch == '.'; ch = read())
cb.append((char) ch);
if (cb.length() == 0)
throw new ConfigException(L.l("unexpected empty type in `{0}'",
_signature));
while (true) {
for (; Character.isWhitespace((char) ch); ch = read()) {
}
if (ch == '[') {
ch = read();
if (ch != ']')
throw new ConfigException(L.l("function syntax is `ret-type name(arg1, ..., argn)' in `{0}'",
_signature));
cb.append("[]");
ch = read();
}
else
break;
}
String className = cb.toString();
unread(ch);
return className;
}
/**
* Skips whitespace to get to the next valid value.
*/
private int skipWhitespace(int ch)
{
for (; Character.isWhitespace((char) ch); ch = read()) {
}
return ch;
}
/**
* Reads the next character.
*/
private int read()
{
if (_index < _signature.length())
return _signature.charAt(_index++);
else
return -1;
}
/**
* Unreads the last character.
*/
private void unread(int ch)
{
if (ch >= 0)
_index--;
}
}