org.wicketstuff.validation.client.AbstractClientAndServerValidatingBehavior.java Source code

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Here is the source code for org.wicketstuff.validation.client.AbstractClientAndServerValidatingBehavior.java

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/**
 * Copyright (C) 2008 Jeremy Thomerson <jeremy@thomersonfamily.com>
 *
 * 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.wicketstuff.validation.client;

import java.util.HashMap;
import java.util.Map;

import org.apache.wicket.Application;
import org.apache.wicket.Component;
import org.apache.wicket.behavior.Behavior;
import org.apache.wicket.markup.head.IHeaderResponse;
import org.apache.wicket.markup.head.JavaScriptHeaderItem;
import org.apache.wicket.markup.head.OnDomReadyHeaderItem;
import org.apache.wicket.markup.head.OnLoadHeaderItem;
import org.apache.wicket.markup.html.form.Form;
import org.apache.wicket.markup.html.form.FormComponent;
import org.apache.wicket.request.resource.PackageResourceReference;
import org.apache.wicket.util.string.JavaScriptUtils;
import org.apache.wicket.util.string.interpolator.MapVariableInterpolator;

/**
 * Abstract validating behavior that all ClientAndServer...Behaviors can extend to provide the base
 * functionality needed to validate on the client side where possible.
 * 
 * @author Jeremy Thomerson
 */
public abstract class AbstractClientAndServerValidatingBehavior<T> extends Behavior {
    private static final long serialVersionUID = 1L;

    private FormComponent<T> mComponent;
    private Form<?> mForm;

    public AbstractClientAndServerValidatingBehavior(Form<?> form) {
        if (form == null) {
            throw new IllegalArgumentException("ClientAndServer validating behaviors require a non-null form");
        }
        mForm = form;
    }

    @SuppressWarnings("unchecked")
    @Override
    public final void bind(Component component) {
        super.bind(component);
        checkComponentIsFormComponent(component);
        mComponent = (FormComponent<T>) component;

        addServerSideValidator(mComponent);

        // make sure that both IDs are rendered
        mComponent.setOutputMarkupId(true);
        mForm.setOutputMarkupId(true);
    }

    protected final void checkComponentIsFormComponent(Component component) {
        if (component instanceof FormComponent == false) {
            throw new IllegalArgumentException(
                    "This behavior [" + getClass().getSimpleName() + "] can only be added to a FormComponent");
        }
    }

    @Override
    public final void renderHead(Component c, IHeaderResponse response) {
        super.renderHead(c, response);

        // add our validation javascript file
        response.render(
                JavaScriptHeaderItem.forReference(new PackageResourceReference(getClass(), "validation.js")));

        // add a trigger that will add our validation to the forms' onSubmit methods
        response.render(OnLoadHeaderItem.forScript("ClientAndServerValidator.addFormOnloadEvents();"));

        CharSequence formID = jsEscape(mForm.getMarkupId());
        CharSequence compID = jsEscape(mComponent.getMarkupId());
        String message = Application.get().getResourceSettings().getLocalizer().getString(getResourceKey(),
                mComponent);
        Map<String, Object> vars = variablesMap(mForm, mComponent);
        boolean thrExc = Application.get().getResourceSettings().getThrowExceptionOnMissingResource();
        MapVariableInterpolator mvi = new MapVariableInterpolator(message, vars, thrExc);
        CharSequence escapedMessage = jsEscape(mvi.toString());

        String validator = createValidatorConstructorJavaScript(formID, compID, escapedMessage);
        String js = "ClientAndServerValidator.registerValidator(" + validator + ");";
        response.render(OnDomReadyHeaderItem.forScript(js));
    }

    protected final CharSequence jsEscape(CharSequence js) {
        // TODO: this may need more escaping
        return JavaScriptUtils.escapeQuotes(js);
    }

    protected String createValidatorConstructorJavaScript(CharSequence formID, CharSequence compID,
            CharSequence escapedMessage) {
        return "new " + getValidatorJSClassName() + "('" + formID + "', '" + compID + "', '" + escapedMessage
                + "')";
    }

    protected String getValidatorJSClassName() {
        return getClass().getSimpleName();
    }

    protected Map<String, Object> variablesMap(Form<?> form, FormComponent<T> component) {
        Map<String, Object> vars = new HashMap<String, Object>();
        vars.put("form", form.getMarkupId());
        vars.put("label", component.getMarkupId());
        vars.put("input", "{VAL}");
        return vars;
    }

    /**
     * @return the resource key where the 'failed' message for this validator can be found
     */
    protected String getResourceKey() {
        return getClass().getSimpleName();
    }

    protected abstract void addServerSideValidator(FormComponent<T> component);

}