CacheFactory.java

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package com.sun.gjc.spi.base.datastructure;

import com.sun.enterprise.util.i18n.StringManager;
import com.sun.gjc.common.DataSourceObjectBuilder;
import com.sun.logging.LogDomains;
import org.glassfish.resourcebase.resources.api.PoolInfo;

import javax.resource.ResourceException;
import java.lang.reflect.Constructor;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Creates an appropriate statement cache datastructure used in the 
 * Resource Adapter.
 * 
 * @author Shalini M
 */
public class CacheFactory {
    protected final static Logger _logger = 
            LogDomains.getLogger(CacheFactory.class, LogDomains.RSR_LOGGER);

    protected final static StringManager localStrings =
            StringManager.getManager(DataSourceObjectBuilder.class);

    public static Cache getDataStructure(PoolInfo poolInfo, String cacheType,
            int maxSize) throws ResourceException {
        Cache stmtCacheStructure;

        if(cacheType == null || cacheType.trim().equals("")) {
            debug("Initializing LRU Cache Implementation");
            stmtCacheStructure = new LRUCacheImpl(poolInfo, maxSize);
        } else if(cacheType.equals("FIXED")) {
            debug("Initializing FIXED Cache Implementation");
            stmtCacheStructure = new FIXEDCacheImpl(poolInfo, maxSize);
        } else { // consider the value of cacheType as a className
            stmtCacheStructure = initCustomCacheStructurePrivileged(cacheType,
                    maxSize);
        } 
        if(!stmtCacheStructure.isSynchronized()) {
            return new SynchronizedCache(stmtCacheStructure);
        }
        return stmtCacheStructure;
    }

    private static Cache initCustomCacheStructurePrivileged(
            final String className, final int cacheSize) throws ResourceException {
        Object result = AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {

                Object result = null;
                try {
                    result = initializeCacheStructure(className, cacheSize);
                } catch (Exception e) {
                    _logger.log(Level.WARNING, localStrings.getString(
                            "jdbc.statement-cache.datastructure.init.failure", 
                            className));
                    _logger.log(Level.WARNING, localStrings.getString(
                            "jdbc.statement-cache.datastructure.init.failure.exception", 
                            e));
                }
                return result;
            }
        });
        if (result != null) {
            return (Cache) result;
        } else {
            throw new ResourceException("Unable to initalize custom DataStructure " +
                    "for Statement Cahe : " + className);
        }
    }

    private static Cache initializeCacheStructure(String className, 
            int maxSize) throws Exception {
        Cache ds;
        Object[] constructorParameters = new Object[]{maxSize};

        Class class1 = Class.forName(className);
        Constructor constructor = class1.getConstructor(class1, Integer.class);
        ds = (Cache) constructor.newInstance(constructorParameters);
        return ds;
    }

    private static void debug(String debugStatement) {
        if(_logger.isLoggable(Level.FINE)) {
            _logger.log(Level.FINE, debugStatement);
        }
    }
}