Convert a given String into the appropriate Class.
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.StringTokenizer;
/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
public class Main {
/** Primitive type name -> class map. */
private static final Map PRIMITIVE_NAME_TYPE_MAP = new HashMap();
/** Setup the primitives map. */
static {
PRIMITIVE_NAME_TYPE_MAP.put("boolean", Boolean.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("byte", Byte.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("char", Character.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("short", Short.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("int", Integer.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("long", Long.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("float", Float.TYPE);
PRIMITIVE_NAME_TYPE_MAP.put("double", Double.TYPE);
}
/**
* Convert a list of Strings from an Interator into an array of Classes (the
* Strings are taken as classnames).
*
* @param it
* A java.util.Iterator pointing to a Collection of Strings
* @param cl
* The ClassLoader to use
*
* @return Array of Classes
*
* @throws ClassNotFoundException
* When a class could not be loaded from the specified ClassLoader
*/
public final static Class<?>[] convertToJavaClasses(Iterator<String> it, ClassLoader cl)
throws ClassNotFoundException {
ArrayList<Class<?>> classes = new ArrayList<Class<?>>();
while (it.hasNext()) {
classes.add(convertToJavaClass(it.next(), cl));
}
return classes.toArray(new Class[classes.size()]);
}
/**
* Convert a given String into the appropriate Class.
*
* @param name
* Name of class
* @param cl
* ClassLoader to use
*
* @return The class for the given name
*
* @throws ClassNotFoundException
* When the class could not be found by the specified ClassLoader
*/
private final static Class convertToJavaClass(String name, ClassLoader cl)
throws ClassNotFoundException {
int arraySize = 0;
while (name.endsWith("[]")) {
name = name.substring(0, name.length() - 2);
arraySize++;
}
// Check for a primitive type
Class c = (Class) PRIMITIVE_NAME_TYPE_MAP.get(name);
if (c == null) {
// No primitive, try to load it from the given ClassLoader
try {
c = cl.loadClass(name);
} catch (ClassNotFoundException cnfe) {
throw new ClassNotFoundException("Parameter class not found: " + name);
}
}
// if we have an array get the array class
if (arraySize > 0) {
int[] dims = new int[arraySize];
for (int i = 0; i < arraySize; i++) {
dims[i] = 1;
}
c = Array.newInstance(c, dims).getClass();
}
return c;
}
}
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