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The source code
/*
* NewFunction.java - creates a new instance
* Copyright (C) 2000 Guillaume Desnoix
* guillaume-desnoix@memoire.com
* http://www.memoire.com/guillaume-desnoix/
*
* This program 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 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 PURSubE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package org.jext.dawn.javaccess;
import org.jext.dawn.*;
import java.lang.reflect.*;
/**
* Create an object.
* Usage:
* class new
* Returns the new instance.
* @author Guillaume Desnoix
*/
public class NewFunction extends Function
{
public NewFunction()
{
super("new");
}
public void invoke(DawnParser parser) throws DawnRuntimeException
{
parser.checkEmpty(this);
Object o = parser.pop();
if (o instanceof Class)
useDefaultConstructor(parser, (Class)o);
else
if (o instanceof Constructor)
invokeConstructor(parser, (Constructor)o);
else
throw new DawnRuntimeException
(this, parser, "" + o + " is not a class or a constructor");
}
private void useDefaultConstructor(DawnParser parser, Class clazz)
throws DawnRuntimeException
{
try
{
Object r = clazz.newInstance();
if (r != null)
{
parser.push(r);
// System.out.println("RESULT="+r);
}
} catch(IllegalAccessException ex) {
throw new DawnRuntimeException(this, parser, "illegal access");
} catch(InstantiationException ex) {
throw new DawnRuntimeException(this, parser, "instantiation failed");
}
}
private void invokeConstructor(DawnParser parser, Constructor c)
throws DawnRuntimeException
{
Class[] t = c.getParameterTypes();
int n = t.length;
parser.checkArgsNumber(this, n);
// this code is the same than invoke() in InvokeFunction.
try
{
Object[] p = new Object[n];
for(int i = n - 1; i >= 0; i--)
p[i] = parser.pop();
for(int i = 0; i < n; i++)
{
if (p[i] == NullFunction.NULL)
p[i] = null;
else if ((t[i] == Integer.TYPE) || (t[i] == Integer.class))
{
if(p[i] instanceof Number)
p[i]=new Integer(((Number)p[i]).intValue());
}
else if ((t[i] == Boolean.TYPE) || (t[i] == Boolean.class))
{
if (p[i] instanceof Number)
p[i] = ((((Number) p[i]).doubleValue() != 0.0) ? Boolean.TRUE : Boolean.FALSE);
else if (!"\"\"".equals(p[i]))
p[i] = Boolean.TRUE;
else
p[i] = Boolean.FALSE;
} else if (t[i] == String.class) {
String s = "" + p[i];
int l = s.length();
if ((l >= 2) && (s.charAt(0) == '\"') && (s.charAt(l - 1) == '\"'))
s = s.substring(1, l - 1);
p[i] = s;
} else if ((t[i] == Float.TYPE) || (t[i] == Float.class)) {
if (p[i] instanceof Number)
p[i] = new Float(((Number) p[i]).floatValue());
} else if ((t[i] == Character.TYPE) || (t[i] == Character.class)) {
if (p[i] instanceof Number)
p[i] = new Character((char) ((Number) p[i]).intValue());
}
else if ((t[i] == Short.TYPE) || (t[i] == Short.class))
{
if(p[i] instanceof Number)
p[i]=new Short(((Number)p[i]).shortValue());
}
}
parser.push(c.newInstance(p));
} catch(IllegalAccessException ex) {
throw new DawnRuntimeException(this, parser, "illegal access");
} catch(InstantiationException ex) {
throw new DawnRuntimeException(this, parser, "instantiation failed");
} catch(InvocationTargetException ex) {
throw new DawnRuntimeException
(this, parser, "invocation failed: " +
ex.getTargetException().getMessage());
}
}
}
// End of NewFunction.java
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