org.apache.wicket.markup.html.form.CheckBox.java Source code

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Here is the source code for org.apache.wicket.markup.html.form.CheckBox.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.wicket.markup.html.form;

import java.util.Locale;

import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.model.IModel;
import org.apache.wicket.util.convert.IConverter;

/**
 * HTML checkbox input component.
 * <p>
 * Java:
 * 
 * <pre>
 * form.add(new CheckBox(&quot;bool&quot;));
 * </pre>
 * 
 * HTML:
 * 
 * <pre>
 *  &lt;input type=&quot;checkbox&quot; wicket:id=&quot;bool&quot; /&gt;
 * </pre>
 * 
 * </p>
 * <p>
 * A CheckBox always has a valid therefore values from methods
 * {@link FormComponent#setRequired(boolean)} and {@link FormComponent#isRequired()} are not taken
 * into account.
 * </p>
 * 
 * @author Jonathan Locke
 */
public class CheckBox extends FormComponent<Boolean> {
    private static final long serialVersionUID = 1L;

    /**
     * @see org.apache.wicket.Component#Component(String)
     */
    public CheckBox(final String id) {
        this(id, null);
    }

    /**
     * @param id
     * @param model
     * @see org.apache.wicket.Component#Component(String, IModel)
     */
    public CheckBox(final String id, IModel<Boolean> model) {
        super(id, model);
        setType(Boolean.class);
    }

    /**
     * Processes the component tag.
     * 
     * @param tag
     *            Tag to modify
     * @see org.apache.wicket.Component#onComponentTag(ComponentTag)
     */
    @Override
    protected void onComponentTag(final ComponentTag tag) {
        checkComponentTag(tag, "input");
        checkComponentTagAttribute(tag, "type", "checkbox");

        final String value = getValue();
        final IConverter<Boolean> converter = getConverter(Boolean.class);
        final Boolean checked = converter.convertToObject(value, getLocale());

        if (Boolean.TRUE.equals(checked)) {
            tag.put("checked", "checked");
        } else {
            // In case the attribute was added at design time
            tag.remove("checked");
        }

        // remove value attribute, because it overrides the browser's submitted value, eg a [input
        // type="checkbox" value=""] will always submit as false
        tag.remove("value");

        super.onComponentTag(tag);
    }

    @Override
    protected IConverter<?> createConverter(Class<?> type) {
        if (Boolean.class.equals(type)) {
            return CheckBoxConverter.INSTANCE;
        }
        return null;
    }

    /**
     * Converter specific to the check box
     * 
     * @author igor.vaynberg
     */
    private static class CheckBoxConverter implements IConverter<Boolean> {
        private static final long serialVersionUID = 1L;

        private static final IConverter<Boolean> INSTANCE = new CheckBoxConverter();

        /**
         * Constructor
         */
        private CheckBoxConverter() {

        }

        /**
         * @see org.apache.wicket.util.convert.IConverter#convertToObject(java.lang.String,
         *      java.util.Locale)
         */
        @Override
        public Boolean convertToObject(String value, Locale locale) {
            if ("on".equals(value) || "true".equals(value)) {
                return Boolean.TRUE;
            } else {
                return Boolean.FALSE;
            }
        }

        /**
         * @see org.apache.wicket.util.convert.IConverter#convertToString(java.lang.Object,
         *      java.util.Locale)
         */
        @Override
        public String convertToString(Boolean value, Locale locale) {
            return value.toString();
        }
    }

    @Override
    public boolean checkRequired() {
        // a checkbox always has a value so this check always passes
        return true;
    }

}