com.swtxml.swt.metadata.WidgetRegistry.java Source code

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Here is the source code for com.swtxml.swt.metadata.WidgetRegistry.java

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/*******************************************************************************
 * Copyright (c) 2008 Ralf Ebert
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Ralf Ebert - initial API and implementation
 *******************************************************************************/
package com.swtxml.swt.metadata;

import java.lang.reflect.Constructor;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.apache.commons.lang.StringUtils;
import org.eclipse.swt.widgets.Widget;

import com.swtxml.definition.DefinitionException;
import com.swtxml.util.lang.CollectionUtils;
import com.swtxml.util.lang.IFilter;
import com.swtxml.util.lang.ResourceUtils;
import com.swtxml.util.parser.ParseException;

public class WidgetRegistry {

    private Map<String, String[]> widgetStylesByClassName = new HashMap<String, String[]>();

    public WidgetRegistry() {
        String widgetClasses = ResourceUtils.toString(ResourceUtils.getClassResource(this.getClass(), "txt"));
        for (String line : StringUtils.split(widgetClasses, "\n")) {
            String[] parts = StringUtils.split(line, '=');
            String className = parts[0].trim();
            String[] allowedStyles = (parts.length > 1) ? StringUtils.split(parts[1].trim(), ", ")
                    : new String[] {};
            widgetStylesByClassName.put(className, allowedStyles);
        }
    }

    public Collection<String> getWidgetClassNames() {
        return widgetStylesByClassName.keySet();
    }

    public Collection<String> getAllowedStylesFor(Class<?> widgetClass) {
        Set<String> allowedStyles = new HashSet<String>();
        do {
            String[] styles = widgetStylesByClassName.get(widgetClass.getName());
            if (styles == null) {
                throw new ParseException("Unknown widget super class: " + widgetClass);
            }
            allowedStyles.addAll(Arrays.asList(styles));
            widgetClass = widgetClass.getSuperclass();
        } while (widgetClass.getSuperclass() != null && !Object.class.equals(widgetClass));
        return allowedStyles;
    }

    @SuppressWarnings("unchecked")
    public Class<? extends Widget> getWidgetClass(String className) {
        try {
            return (Class<? extends Widget>) Class.forName(className);
        } catch (ClassNotFoundException e) {
            throw new DefinitionException(e);
        }
    }

    @SuppressWarnings("unchecked")
    public Constructor getWidgetConstructor(Class<? extends Widget> widgetClass) {
        return CollectionUtils.find(Arrays.asList(widgetClass.getConstructors()), new IFilter<Constructor>() {

            public boolean match(Constructor constructor) {
                return (constructor.getParameterTypes().length == 2
                        && constructor.getParameterTypes()[1] == Integer.TYPE);
            }

        });
    }

    public Class<?> getAllowedParentType(Class<? extends Widget> type) {
        Constructor<?> constructor = getWidgetConstructor(type);
        return constructor.getParameterTypes()[0];

    }
}