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Commons DBCP example source code file (InstanceKeyObjectFactory.java)

This example Commons DBCP source code file (InstanceKeyObjectFactory.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons DBCP tags/keywords

classnotfoundexception, hashtable, instancekeydatasource, instancekeydatasource, io, ioexception, ioexception, iterator, naming, object, object, objectinputstream, refaddr, reference, string, string, util

The Commons DBCP InstanceKeyObjectFactory.java source code

/*
 * 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.commons.dbcp.datasources;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.ObjectInputStream;

import java.util.Hashtable;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Properties;

import javax.naming.Context;
import javax.naming.Name;
import javax.naming.RefAddr;
import javax.naming.Reference;
import javax.naming.spi.ObjectFactory;

/**
 * A JNDI ObjectFactory which creates <code>SharedPoolDataSources
 * or <code>PerUserPoolDataSources
 *
 * @version $Revision: 814246 $ $Date: 2009-09-12 18:44:58 -0400 (Sat, 12 Sep 2009) $
 */
abstract class InstanceKeyObjectFactory
    implements ObjectFactory
{
    private static final Map instanceMap = new HashMap();

    synchronized static String registerNewInstance(InstanceKeyDataSource ds) {
        int max = 0;
        Iterator i = instanceMap.keySet().iterator();
        while (i.hasNext()) {
            Object obj = i.next();
            if (obj instanceof String)
            {
                try {
                    max = Math.max(max, Integer.valueOf((String)obj).intValue());
                }
                catch (NumberFormatException e) {
                    // no sweat, ignore those keys
                }
            }
        }
        String instanceKey = String.valueOf(max + 1);
        // put a placeholder here for now, so other instances will not
        // take our key.  we will replace with a pool when ready.
        instanceMap.put(instanceKey, ds);
        return instanceKey;
    }

    static void removeInstance(String key)
    {
        instanceMap.remove(key);
    }

    /**
     * Close all pools associated with this class.
     */
    public static void closeAll() throws Exception {
        //Get iterator to loop over all instances of this datasource.
        Iterator instanceIterator = instanceMap.entrySet().iterator();
        while (instanceIterator.hasNext()) {
            ((InstanceKeyDataSource)
                ((Map.Entry) instanceIterator.next()).getValue()).close();
        }
        instanceMap.clear();
    }


    /**
     * implements ObjectFactory to create an instance of SharedPoolDataSource
     * or PerUserPoolDataSource
     */
    public Object getObjectInstance(Object refObj, Name name,
                                    Context context, Hashtable env)
        throws IOException, ClassNotFoundException {
        // The spec says to return null if we can't create an instance
        // of the reference
        Object obj = null;
        if (refObj instanceof Reference) {
            Reference ref = (Reference) refObj;
            if (isCorrectClass(ref.getClassName())) {
                RefAddr ra = ref.get("instanceKey");
                if (ra != null && ra.getContent() != null) {
                    // object was bound to jndi via Referenceable api.
                    obj = instanceMap.get(ra.getContent());
                }
                else
                {
                    // tomcat jndi creates a Reference out of server.xml
                    // <ResourceParam> configuration and passes it to an
                    // instance of the factory given in server.xml.
                    String key = null;
                    if (name != null)
                    {
                        key = name.toString();
                        obj = instanceMap.get(key);
                    }
                    if (obj == null)
                    {
                        InstanceKeyDataSource ds = getNewInstance(ref);
                        setCommonProperties(ref, ds);
                        obj = ds;
                        if (key != null)
                        {
                            instanceMap.put(key, ds);
                        }
                    }
                }
            }
        }
        return obj;
    }

    private void setCommonProperties(Reference ref,
                                     InstanceKeyDataSource ikds)
        throws IOException, ClassNotFoundException {

        RefAddr ra = ref.get("dataSourceName");
        if (ra != null && ra.getContent() != null) {
            ikds.setDataSourceName(ra.getContent().toString());
        }

        ra = ref.get("defaultAutoCommit");
        if (ra != null && ra.getContent() != null) {
            ikds.setDefaultAutoCommit(Boolean.valueOf(
                ra.getContent().toString()).booleanValue());
        }

        ra = ref.get("defaultReadOnly");
        if (ra != null && ra.getContent() != null) {
            ikds.setDefaultReadOnly(Boolean.valueOf(
                ra.getContent().toString()).booleanValue());
        }

        ra = ref.get("description");
        if (ra != null && ra.getContent() != null) {
            ikds.setDescription(ra.getContent().toString());
        }

        ra = ref.get("jndiEnvironment");
        if (ra != null  && ra.getContent() != null) {
            byte[] serialized = (byte[]) ra.getContent();
            ikds.jndiEnvironment =
                (Properties) deserialize(serialized);
        }

        ra = ref.get("loginTimeout");
        if (ra != null && ra.getContent() != null) {
            ikds.setLoginTimeout(
                Integer.parseInt(ra.getContent().toString()));
        }

        ra = ref.get("testOnBorrow");
        if (ra != null && ra.getContent() != null) {
            ikds.setTestOnBorrow(Boolean.valueOf(
                ra.getContent().toString()).booleanValue());
        }

        ra = ref.get("testOnReturn");
        if (ra != null && ra.getContent() != null) {
            ikds.setTestOnReturn(Boolean.valueOf(
                ra.getContent().toString()).booleanValue());
        }

        ra = ref.get("timeBetweenEvictionRunsMillis");
        if (ra != null && ra.getContent() != null) {
            ikds.setTimeBetweenEvictionRunsMillis(
                Integer.parseInt(ra.getContent().toString()));
        }

        ra = ref.get("numTestsPerEvictionRun");
        if (ra != null && ra.getContent() != null) {
            ikds.setNumTestsPerEvictionRun(
                Integer.parseInt(ra.getContent().toString()));
        }

        ra = ref.get("minEvictableIdleTimeMillis");
        if (ra != null && ra.getContent() != null) {
            ikds.setMinEvictableIdleTimeMillis(
                Integer.parseInt(ra.getContent().toString()));
        }

        ra = ref.get("testWhileIdle");
        if (ra != null && ra.getContent() != null) {
            ikds.setTestWhileIdle(Boolean.valueOf(
                ra.getContent().toString()).booleanValue());
        }

        ra = ref.get("validationQuery");
        if (ra != null && ra.getContent() != null) {
            ikds.setValidationQuery(ra.getContent().toString());
        }
    }


    /**
     * @return true if and only if className is the value returned
     * from getClass().getName().toString()
     */
    protected abstract boolean isCorrectClass(String className);

    /**
     * Creates an instance of the subclass and sets any properties
     * contained in the Reference.
     */
    protected abstract InstanceKeyDataSource getNewInstance(Reference ref)
        throws IOException, ClassNotFoundException;

    /**
     * used to set some properties saved within a Reference
     */
    protected static final Object deserialize(byte[] data)
        throws IOException, ClassNotFoundException {
        ObjectInputStream in = null;
        try {
            in = new ObjectInputStream(new ByteArrayInputStream(data));
            return in.readObject();
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (IOException ex) {
                }
            }
        }
    }
}

Other Commons DBCP examples (source code examples)

Here is a short list of links related to this Commons DBCP InstanceKeyObjectFactory.java source code file:

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