org.wso2.carbon.connector.FileAppendConnector.java Source code

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Here is the source code for org.wso2.carbon.connector.FileAppendConnector.java

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/*
* Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. 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.wso2.carbon.connector;

import java.io.IOException;
import java.io.OutputStream;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemException;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.synapse.MessageContext;

import org.apache.synapse.SynapseException;
import org.wso2.carbon.connector.core.AbstractConnector;
import org.wso2.carbon.connector.core.util.ConnectorUtils;
import org.wso2.carbon.connector.util.FileConnectorUtils;
import org.wso2.carbon.connector.util.FileConstants;
import org.wso2.carbon.connector.util.ResultPayloadCreator;

/**
 * This class is used to append file content.
 */
public class FileAppendConnector extends AbstractConnector {
    private static final Log log = LogFactory.getLog(FileAppendConnector.class);

    /**
     * Initiate the appendFile method.
     *
     * @param messageContext The message context that is used in file append mediation flow.
     */
    public void connect(MessageContext messageContext) {
        try {
            ResultPayloadCreator.generateResult(messageContext, appendFile(messageContext));
        } catch (FileSystemException e) {
            throw new SynapseException("Error while appending the content", e);
        }
    }

    /**
     * Add the content into file.
     *
     * @param messageContext The message context that is generated for processing the file.
     * @return true, if the content is successfully appended.
     * @throws FileSystemException On error parsing the file name, determining if the file exists and creating the
     * file.
     */
    private boolean appendFile(MessageContext messageContext) throws FileSystemException {
        String destination = (String) ConnectorUtils.lookupTemplateParamater(messageContext,
                FileConstants.NEW_FILE_LOCATION);
        String content = (String) ConnectorUtils.lookupTemplateParamater(messageContext, FileConstants.CONTENT);
        String encoding = (String) ConnectorUtils.lookupTemplateParamater(messageContext, FileConstants.ENCODING);
        if (StringUtils.isEmpty(encoding)) {
            encoding = FileConstants.DEFAULT_ENCODING;
        }
        FileSystemOptions opts = FileConnectorUtils.init(messageContext);
        OutputStream out = null;
        FileObject fileObj = null;
        StandardFileSystemManager manager = FileConnectorUtils.getManager();
        try {
            fileObj = manager.resolveFile(destination, opts);
            if (!fileObj.exists()) {
                fileObj.createFile();
            }
            // True, if the content should be appended.
            out = fileObj.getContent().getOutputStream(true);
            IOUtils.write(content, out, encoding);
            if (log.isDebugEnabled()) {
                log.debug("File appending completed. " + destination);
            }
        } catch (IOException e) {
            throw new SynapseException("Error while appending content", e);
        } finally {
            try {
                if (fileObj != null) {
                    // close the file object
                    fileObj.close();
                }
            } catch (FileSystemException e) {
                log.error("Error while closing FileObject", e);
            }
            try {
                if (out != null) {
                    // close the output stream
                    out.close();
                }
            } catch (IOException e) {
                log.error("Error while closing OutputStream", e);
            }
            // close the StandardFileSystemManager
            manager.close();
        }
        return true;
    }
}