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Tools to be used in a servlet context.
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package org.apache.velocity.tools.view;

/*
 * 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.
 */

import org.apache.velocity.tools.Scope;
import org.apache.velocity.tools.config.DefaultKey;
import org.apache.velocity.tools.config.ValidScope;
import org.apache.velocity.tools.generic.ValueParser;

/**
 * General-purpose text-importing view tool for templates.
 * Usage:

 * Just call $import.read("http://www.foo.com/bleh.jsp?sneh=bar") to insert the contents of the named
 * resource into the template.
 * 
 *  * Toolbox configuration:
 * <tools>
 *   <toolbox scope="request">
 *     <tool class="org.apache.velocity.tools.view.ImportTool"/>
 *   </toolbox>
 * </tools>
 * 
 *
 * @author Marino A. Jonsson
 * @since VelocityTools 2.0
 * @version $Revision$ $Date$
 */

@DefaultKey("import")
@ValidScope(Scope.REQUEST)
public class ImportTool extends org.apache.velocity.tools.generic.ImportTool
{
    private static final long serialVersionUID = 9071583951325800486L;

    protected synchronized void initializeImportSupport(ValueParser config)
    {
        if (importSupport == null)
        {
            importSupport = new ViewImportSupport();
            importSupport.configure(config);
        }
    }

    protected void configure(ValueParser values)
    {
        super.configure(values);
    }

    /**
     * Returns the supplied URL rendered as a String.
     *
     * @param obj the URL to import
     * @return the URL as a string
     */
    public String read(Object obj) {
        if (obj == null)
        {
            getLog().warn("URL is null!");
            return null;
        }
        String url = String.valueOf(obj).trim();
        if (url.length() == 0)
        {
            getLog().warn("URL is empty string!");
            return null;
        }
        try
        {
            return importSupport.acquireString(url);
        }
        catch (Exception ex)
        {
            getLog().error("Exception while acquiring '{}'", url, ex);
            return null;
        }
    }
}