getresourceinputstreamaction.java

derby database source code.good for you.

/*

   Derby - Class org.apache.derby.client.am.GetResourceInputStreamAction

   Copyright (c) 2003, 2005 The Apache Software Foundation or its licensors, where applicable.

   Licensed 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.derby.client.am;

/**
 * Java 2 PrivilegedAction encapsulation of attempting to acquire driver-general properties as a System resource.
 */
public class GetResourceInputStreamAction implements java.security.PrivilegedAction {
    // Name for loading the resource.
    private String resourceName_ = null;
    // Path of the resource being loaded.
    private String resourcePath_ = null;
    // Class loader being used to load the resource.
    private String resourceLoaderId_ = null;

    //-------------------- Constructors --------------------

    public GetResourceInputStreamAction(String resourceName) {
        resourceName_ = resourceName;
    }

    //-------------------- methods --------------------

    public Object run() {
        try {
            ClassLoader contextLoader = Thread.currentThread().getContextClassLoader();
            if (contextLoader != null) {
                java.net.URL resourceUrl = contextLoader.getResource(resourceName_);
                if (resourceUrl != null) {
                    resourcePath_ = resourceUrl.getPath();
                    resourceLoaderId_ = "Context ClassLoader: " + contextLoader;
                    return contextLoader.getResourceAsStream(resourceName_);
                }
            }
            ClassLoader thisLoader = getClass().getClassLoader();
            if (thisLoader != contextLoader) {
                java.net.URL resourceUrl = thisLoader.getResource(resourceName_);
                if (resourceUrl != null) {
                    resourcePath_ = resourceUrl.getPath();
                    resourceLoaderId_ = "Driver ClassLoader: " + thisLoader;
                    return thisLoader.getResourceAsStream(resourceName_);
                }
            }
            ClassLoader systemLoader = ClassLoader.getSystemClassLoader();
            if (systemLoader != contextLoader &&
                    systemLoader != thisLoader) {
                java.net.URL resourceUrl = systemLoader.getResource(resourceName_);
                if (resourceUrl != null) {
                    resourcePath_ = resourceUrl.getPath();
                    resourceLoaderId_ = "System ClassLoader: " + systemLoader;
                    return systemLoader.getResourceAsStream(resourceName_);
                }
            }
            return null;
        } catch (java.security.AccessControlException ace) {
            // This happens in an Applet environment,
            // so return with null.
            return null;
        }
    }

    public void setResourceName(String resourceName) {
        resourceName_ = resourceName;
    }

    public String getResourcePath() {
        return resourcePath_;
    }

    public String getResourceLoaderId() {
        return resourceLoaderId_;
    }

}