Re: svn commit: r1676970 - /ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java

[Adrian Crum-3]

Hmmm... this seems to have a caused a problem with the load-demo ant
target. I am looking into it.

Adrian Crum
Sandglass Software
www.sandglass-software.com

On 4/30/2015 1:12 PM, [hidden email] wrote:

> Author: adrianc
> Date: Thu Apr 30 12:12:17 2015
> New Revision: 1676970
>
> URL: http://svn.apache.org/r1676970
> Log:
> Some work on ComponentLoaderConfig.java:
>
> 1. Thread safety
> 2. Optimization
> 3. Code cleanup
> 4. Improved error handling
>
> Modified:
>      ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java
>
> Modified: ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java
> URL: http://svn.apache.org/viewvc/ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java?rev=1676970&r1=1676969&r2=1676970&view=diff
> ==============================================================================
> --- ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java (original)
> +++ ofbiz/trunk/framework/base/src/org/ofbiz/base/component/ComponentLoaderConfig.java Thu Apr 30 12:12:17 2015
> @@ -20,15 +20,15 @@ package org.ofbiz.base.component;
>
>   import java.io.IOException;
>   import java.net.URL;
> -import java.util.LinkedList;
> +import java.util.ArrayList;
>   import java.util.List;
> -import java.util.Properties;
> +import java.util.Map;
> +import java.util.concurrent.atomic.AtomicReference;
>
>   import javax.xml.parsers.ParserConfigurationException;
>
>   import org.ofbiz.base.util.UtilGenerics;
>   import org.ofbiz.base.util.UtilURL;
> -import org.ofbiz.base.util.UtilValidate;
>   import org.ofbiz.base.util.UtilXml;
>   import org.ofbiz.base.util.string.FlexibleStringExpander;
>   import org.w3c.dom.Document;
> @@ -43,33 +43,31 @@ public class ComponentLoaderConfig {
>
>       public static final String module = ComponentLoaderConfig.class.getName();
>       public static final String COMPONENT_LOAD_XML_FILENAME = "component-load.xml";
> -
>       public static final int SINGLE_COMPONENT = 0;
>       public static final int COMPONENT_DIRECTORY = 1;
> -
> -    protected static List<ComponentDef> componentsToLoad = null;
> +    private static final AtomicReference<List<ComponentDef>> componentDefsRef = new AtomicReference<List<ComponentDef>>(null);
>
>       public static List<ComponentDef> getRootComponents(String configFile) throws ComponentException {
> -        if (componentsToLoad == null) {
> -            synchronized (ComponentLoaderConfig.class) {
> -                if (componentsToLoad == null) {
> -                    if (configFile == null) {
> -                        configFile = COMPONENT_LOAD_XML_FILENAME;
> -                    }
> -                    URL xmlUrl = UtilURL.fromResource(configFile);
> -                    ComponentLoaderConfig.componentsToLoad = ComponentLoaderConfig.getComponentsFromConfig(xmlUrl);
> -                }
> +        List<ComponentDef> existingInstance = componentDefsRef.get();
> +        if (existingInstance == null) {
> +            if (configFile == null) {
> +                configFile = COMPONENT_LOAD_XML_FILENAME;
> +            }
> +            URL xmlUrl = UtilURL.fromResource(configFile);
> +            List<ComponentDef> newInstance = getComponentsFromConfig(xmlUrl);
> +            if (componentDefsRef.compareAndSet(existingInstance, newInstance)) {
> +                existingInstance = newInstance;
> +            } else {
> +                existingInstance = componentDefsRef.get();
>               }
>           }
> -        return componentsToLoad;
> +        return existingInstance;
>       }
>
>       public static List<ComponentDef> getComponentsFromConfig(URL configUrl) throws ComponentException {
>           if (configUrl == null) {
> -            throw new ComponentException("Component config file does not exist: " + configUrl);
> +            throw new IllegalArgumentException("configUrl cannot be null");
>           }
> -
> -        List<ComponentDef> componentsFromConfig = null;
>           Document document = null;
>           try {
>               document = UtilXml.readXmlDocument(configUrl, true);
> @@ -80,13 +78,27 @@ public class ComponentLoaderConfig {
>           } catch (IOException e) {
>               throw new ComponentException("Error reading the component config file: " + configUrl, e);
>           }
> -
>           Element root = document.getDocumentElement();
>           List<? extends Element> toLoad = UtilXml.childElementList(root);
> -        if (UtilValidate.isNotEmpty(toLoad)) {
> -            componentsFromConfig = new LinkedList<ComponentDef>();
> -            for (Element element: toLoad) {
> -                componentsFromConfig.add(new ComponentDef(element));
> +        List<ComponentDef> componentsFromConfig = null;
> +        if (!toLoad.isEmpty()) {
> +            componentsFromConfig = new ArrayList<ComponentDef>(toLoad.size());
> +            Map<String, ? extends Object> systemProps = UtilGenerics.<String, Object> checkMap(System.getProperties());
> +            for (Element element : toLoad) {
> +                String nodeName = element.getNodeName();
> +                String name = null;
> +                String location = null;
> +                int type = SINGLE_COMPONENT;
> +                if ("load-component".equals(nodeName)) {
> +                    name = element.getAttribute("component-name");
> +                    location = FlexibleStringExpander.expandString(element.getAttribute("component-location"), systemProps);
> +                } else if ("load-components".equals(nodeName)) {
> +                    location = FlexibleStringExpander.expandString(element.getAttribute("parent-directory"), systemProps);
> +                    type = COMPONENT_DIRECTORY;
> +                } else {
> +                    throw new ComponentException("Invalid element '" + nodeName + "' found in component config file " + configUrl);
> +                }
> +                componentsFromConfig.add(new ComponentDef(name, location, type));
>               }
>           }
>           return componentsFromConfig;
> @@ -94,20 +106,13 @@ public class ComponentLoaderConfig {
>
>       public static class ComponentDef {
>           public String name;
> -        public String location;
> -        public int type = -1;
> +        public final String location;
> +        public final int type;
>
> -        public ComponentDef(Element element) {
> -            Properties systemProps = System.getProperties();
> -            if ("load-component".equals(element.getNodeName())) {
> -                name = element.getAttribute("component-name");
> -                location = FlexibleStringExpander.expandString(element.getAttribute("component-location"), UtilGenerics.<String, Object>checkMap(systemProps));
> -                type = SINGLE_COMPONENT;
> -            } else if ("load-components".equals(element.getNodeName())) {
> -                name = null;
> -                location = FlexibleStringExpander.expandString(element.getAttribute("parent-directory"), UtilGenerics.<String, Object>checkMap(systemProps));
> -                type = COMPONENT_DIRECTORY;
> -            }
> +        private ComponentDef(String name, String location, int type) {
> +            this.name = name;
> +            this.location = location;
> +            this.type = type;
>           }
>       }
>   }
>
>