/*
* 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.ejb.cfg;
import com.caucho.config.ConfigException;
import com.caucho.util.CharBuffer;
import com.caucho.util.L10N;
import java.util.ArrayList;
/**
* A builtin SQL function expression
*/
public class FunctionSignature {
static L10N L = new L10N(FunctionSignature.class);
private String _signature;
// function name
private String _name;
// arguments
private Class []_parameterTypes;
// return type
private Class _returnType;
private int _index;
private String _sql;
/**
* Creates a function definition.
*
* @param signature the function signature in java syntax
*/
public FunctionSignature(String signature)
throws ConfigException
{
_signature = signature;
parseSignature();
}
/**
* Returns the function name.
*/
public String getName()
{
return _name;
}
/**
* Returns the function signature.
*/
public String getSignature()
{
return _signature;
}
/**
* Returns the function arguments.
*/
public Class []getParameterTypes()
{
return _parameterTypes;
}
/**
* Returns the return type;
*/
public Class getReturnType()
{
return _returnType;
}
/**
* Sets the SQL.
*/
public void setSQL(String sql)
{
_sql = sql;
}
/**
* Gets the SQL.
*/
public String getSQL()
{
return _sql;
}
/**
* Parses the function signature.
*/
private void parseSignature()
throws ConfigException
{
_index = 0;
_returnType = parseType(skipWhitespace(read()));
CharBuffer cb = CharBuffer.allocate();
int ch = skipWhitespace(read());
for (; Character.isJavaIdentifierPart((char) ch); ch = read())
cb.append((char) ch);
if (cb.length() == 0)
throw new ConfigException(L.l("unexpected empty function name in '{0}'",
_signature));
_name = cb.toString();
ch = skipWhitespace(ch);
if (ch != '(')
throw new ConfigException(L.l("function syntax is 'ret-type name(arg1, ..., argn)' in '{0}'",
_signature));
ArrayList<Class> argList = new ArrayList<Class>();
ch = read();
while (Character.isJavaIdentifierStart((char) (ch = skipWhitespace(ch)))) {
Class type = parseType(ch);
argList.add(type);
ch = skipWhitespace(read());
if (ch == ',')
ch = read();
}
_parameterTypes = argList.toArray(new Class[argList.size()]);
if (ch != ')')
throw new ConfigException(L.l("function syntax is 'ret-type name(arg1, ..., argn)' in '{0}'",
_signature));
ch = skipWhitespace(read());
if (ch != -1)
throw new ConfigException(L.l("function syntax is 'ret-type name(arg1, ..., argn)' in '{0}'",
_signature));
}
/**
* Parses the type.
*/
private Class parseType(int ch)
throws ConfigException
{
CharBuffer cb = CharBuffer.allocate();
for (; Character.isJavaIdentifierPart((char) ch); ch = read())
cb.append((char) ch);
if (cb.length() == 0)
throw new ConfigException(L.l("unexpected empty type in '{0}'",
_signature));
String className = cb.toString();
unread(ch);
return findClass(className);
}
/**
* Converts the type to a classname.
*/
private Class findClass(String className)
throws ConfigException
{
if ("int".equals(className))
return int.class;
else if ("boolean".equals(className))
return boolean.class;
else if ("double".equals(className))
return double.class;
else if ("String".equals(className))
return String.class;
else if ("Date".equals(className))
return java.util.Date.class;
else if ("any".equals(className))
return Object.class;
throw new ConfigException(L.l("unknown type '{0}' in '{1}'",
className, _signature));
}
/**
* 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--;
}
/**
* Returns a hash-code.
*/
public int hashCode()
{
return _name.hashCode();
}
/**
* True if the function signatures are equal.
*/
public boolean equals(Object o)
{
if (! (o instanceof FunctionSignature))
return false;
FunctionSignature sig = (FunctionSignature) o;
if (! _name.equalsIgnoreCase(sig._name))
return false;
if (_parameterTypes.length != sig._parameterTypes.length)
return false;
for (int i = 0; i < _parameterTypes.length; i++)
if (! _parameterTypes[i].equals(sig._parameterTypes[i]))
return false;
return true;
}
/**
* Returns a string value.
*/
public String toString()
{
return "Function[" + _signature + "]";
}
}