/*******************************************************************************
*
* Struts2-Conversation-Plugin - An Open Source Conversation- and Flow-Scope Solution for Struts2-based Applications
* =================================================================================================================
*
* Copyright (C) 2012 by Rees Byars
* http://code.google.com/p/struts2-conversation/
*
* **********************************************************************************************************************
*
* 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.
*
* **********************************************************************************************************************
*
* $Id: StrutsActionProvider.java reesbyars $
******************************************************************************/
package com.google.code.rees.scope.struts2;
import java.io.IOException;
import java.net.URL;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.struts2.StrutsConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.code.rees.scope.ActionProvider;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.FileManager;
import com.opensymphony.xwork2.FileManagerFactory;
import com.opensymphony.xwork2.inject.Container;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.TextParseUtil;
import com.opensymphony.xwork2.util.classloader.ReloadingClassLoader;
import com.opensymphony.xwork2.util.finder.ClassFinder;
import com.opensymphony.xwork2.util.finder.ClassFinder.ClassInfo;
import com.opensymphony.xwork2.util.finder.ClassLoaderInterface;
import com.opensymphony.xwork2.util.finder.ClassLoaderInterfaceDelegate;
import com.opensymphony.xwork2.util.finder.Test;
import com.opensymphony.xwork2.util.finder.UrlSet;
/**
* Struts2 implementation of the {@link ActionProvider}.
*
* @author rees.byars with code from the struts2 convention package
*/
public class StrutsActionProvider implements ActionProvider {
private static final long serialVersionUID = 6728107973559862449L;
private static final Logger LOG = LoggerFactory.getLogger(StrutsActionProvider.class);
private Set<Class<?>> actionClasses;
private String[] actionPackages;
private String[] packageLocators;
private String[] includeJars;
private boolean disablePackageLocatorsScanning;
private boolean checkImplementsAction;
private String packageLocatorsBasePackage;
private String actionSuffix;
private Set<String> fileProtocols;
private boolean devMode;
private ReloadingClassLoader reloadingClassLoader;
private boolean reload;
private boolean excludeParentClassLoader;
private boolean requireFollowsConvention;
private FileManager fileManager;
private Container container;
public Set<Class<?>> getActionClasses() throws Exception {
try {
if (this.fileManager == null) {
//retrieve this way instead of by injection in order to catch an handle errors/exceptions with older versions of struts2
this.fileManager = this.container.getInstance(FileManagerFactory.class).getFileManager();
}
if (actionClasses == null) {
initReloadClassLoader();
actionClasses = this.findActions();
}
return this.actionClasses;
//This is a hack to make sure that changes to Struts2 classes used below don't blow up the whole plugin
} catch (Throwable t) {
throw new Exception("Could not load action classes on startup. Configuration caches will be built on-demand.");
}
}
@Inject
public void setContainer(Container container) {
this.container = container;
}
@Inject(StrutsConstants.STRUTS_DEVMODE)
public void setDevMode(String mode) {
this.devMode = "true".equals(mode);
}
/**
* Reload configuration when classes change. Defaults to "false" and should
* not be used in production.
*/
@Inject(ConventionConstants.RELOAD_CLASSES)
public void setReload(String reload) {
this.reload = "true".equals(reload);
}
/**
* Exclude URLs found by the parent class loader. Defaults to "true", set to
* true for JBoss
*/
@Inject(ConventionConstants.EXCLUDE_PARENT_CLASS_LOADER)
public void setExcludeParentClassLoader(String exclude) {
this.excludeParentClassLoader = "true".equals(exclude);
}
/**
* File URLs whose protocol are in these list will be processed as jars
* containing classes
*
* @param fileProtocols
* Comma separated list of file protocols that will be considered
* as jar files and scanned
*/
@Inject(ConventionConstants.FILE_PROTOCOLS)
public void setFileProtocols(String fileProtocols) {
if (StringUtils.isNotBlank(fileProtocols)) {
this.fileProtocols = TextParseUtil
.commaDelimitedStringToSet(fileProtocols);
}
}
/**
* @param includeJars
* Comma separated list of regular expressions of jars to be
* included.
*/
@Inject(value = ConventionConstants.INCLUDE_JARS, required = false)
public void setIncludeJars(String includeJars) {
if (StringUtils.isNotEmpty(includeJars))
this.includeJars = includeJars.split("\\s*[,]\\s*");
}
/**
* @param disablePackageLocatorsScanning
* If set to true, only the named packages will be scanned
*/
@Inject(
value = ConventionConstants.PACKAGE_LOCATORS_DISABLE,
required = false)
public void setDisablePackageLocatorsScanning(
String disablePackageLocatorsScanning) {
this.disablePackageLocatorsScanning = "true"
.equals(disablePackageLocatorsScanning);
}
/**
* @param actionPackages
* (Optional) An optional list of action packages that this
* should create configuration for.
*/
@Inject(value = ConventionConstants.ACTION_PACKAGES, required = false)
public void setActionPackages(String actionPackages) {
if (StringUtils.isNotBlank(actionPackages)) {
this.actionPackages = actionPackages.split("\\s*[,]\\s*");
}
}
/**
* @param checkImplementsAction
* (Optional) Map classes that implement
* com.opensymphony.xwork2.Action as actions
*/
@Inject(
value = ConventionConstants.CHECK_IMPLEMENTS_ACTION,
required = false)
public void setCheckImplementsAction(String checkImplementsAction) {
this.checkImplementsAction = "true".equals(checkImplementsAction);
}
/**
* @param actionSuffix
* (Optional) Classes that end with these value will be mapped as
* actions (defaults to "Action")
*/
@Inject(value = ConventionConstants.ACTION_SUFFIX, required = false)
public void setActionSuffix(String actionSuffix) {
if (StringUtils.isNotBlank(actionSuffix)) {
this.actionSuffix = actionSuffix;
}
}
/**
* @param packageLocators
* (Optional) A list of names used to find action packages.
*/
@Inject(value = ConventionConstants.PACKAGE_LOCATORS, required = false)
public void setPackageLocators(String packageLocators) {
this.packageLocators = packageLocators.split("\\s*[,]\\s*");
}
/**
* @param packageLocatorsBasePackage
* (Optional) If set, only packages that start with this name
* will be scanned for actions.
*/
@Inject(
value = ConventionConstants.PACKAGE_LOCATORS_BASE_PACKAGE,
required = false)
public void setPackageLocatorsBase(String packageLocatorsBasePackage) {
this.packageLocatorsBasePackage = packageLocatorsBasePackage;
}
/**
* @param requireFollowsConvention
* If true, only classes that follow the convention for action
* classes will
* be scanned for the scope annotations.
*/
@Inject(value = StrutsScopeConstants.REQUIRE_FOLLOWS_CONVENTION)
public void setRequireFollowsConvention(String requireFollowsConvention) {
this.requireFollowsConvention = "true".equals(requireFollowsConvention);
}
/**
* Note that we can't include the test for {@link #actionSuffix} here
* because a class is included if its name ends in {@link #actionSuffix} OR
* it implements {@link com.opensymphony.xwork2.Action}. Since the whole
* goal is to avoid loading the class if we don't have to, the (actionSuffix
* || implements Action) test will have to remain until later. See
* {@link #getActionClassTest()} for the test performed on the loaded
* {@link ClassInfo} structure.
*
* @param className
* the name of the class to test
* @return true if the specified class should be included in the
* package-based action scan
*/
protected boolean includeClassNameInActionScan(String className) {
String classPackageName = StringUtils.substringBeforeLast(className,
".");
if (actionPackages != null) {
for (String packageName : actionPackages) {
String strictPackageName = packageName + ".";
if (classPackageName.equals(packageName)
|| classPackageName.startsWith(strictPackageName))
return true;
}
}
if (packageLocators != null && !disablePackageLocatorsScanning) {
for (String packageLocator : packageLocators) {
if (classPackageName.length() > 0
&& (packageLocatorsBasePackage == null || classPackageName
.startsWith(packageLocatorsBasePackage))) {
String[] splitted = classPackageName.split("\\.");
if (contains(splitted, packageLocator, false))
return true;
}
}
}
return false;
}
/**
* Construct a {@link Test} object that determines if a specified class name
* should be included in the package scan based on the clazz's package name.
* Note that the goal is to avoid loading the class, so the test should only
* rely on information in the class name itself. The default implementation
* is to return the result of {@link #includeClassNameInActionScan(String)}.
*
* @return a {@link Test} object that returns true if the specified class
* name should be included in the package scan
*/
protected Test<String> getClassPackageTest() {
return new Test<String>() {
public boolean test(String className) {
return includeClassNameInActionScan(className);
}
};
}
/**
* Construct a {@link Test} Object that determines if a specified class
* should be included in the package scan based on the full
* {@link ClassInfo} of the class. At this point, the class has been loaded,
* so it's ok to perform tests such as checking annotations or looking at
* interfaces or super-classes of the specified class.
*
* @return a {@link Test} object that returns true if the specified class
* should be included in the package scan
*/
protected Test<ClassFinder.ClassInfo> getActionClassTest() {
return new Test<ClassFinder.ClassInfo>() {
public boolean test(ClassFinder.ClassInfo classInfo) {
// Why do we call includeClassNameInActionScan here, when it's
// already been called to in the initial call to ClassFinder?
// When some action class passes our package filter in that
// step,
// ClassFinder automatically includes parent classes of that
// action,
// such as com.opensymphony.xwork2.ActionSupport. We repeat the
// package filter here to filter out such results.
boolean inPackage = includeClassNameInActionScan(classInfo
.getName());
boolean nameMatches = classInfo.getName()
.endsWith(actionSuffix) || !requireFollowsConvention;
try {
return inPackage
&& (nameMatches || (checkImplementsAction && com.opensymphony.xwork2.Action.class
.isAssignableFrom(classInfo.get())));
} catch (ClassNotFoundException ex) {
if (LOG.isErrorEnabled())
LOG.error("Unable to load class [#0]", ex,
classInfo.getName());
return false;
}
}
};
}
protected Set<Class<?>> findActions() {
Set<Class<?>> classes = new HashSet<Class<?>>();
try {
if (actionPackages != null
|| (packageLocators != null && !disablePackageLocatorsScanning)) {
// By default, ClassFinder scans EVERY class in the specified
// url set, which can produce spurious warnings for non-action
// classes that can't be loaded. We pass a package filter that
// only considers classes that match the action packages
// specified by the user
Test<String> classPackageTest = getClassPackageTest();
ClassFinder finder = new ClassFinder(getClassLoaderInterface(),
buildUrlSet().getUrls(), true, this.fileProtocols,
classPackageTest);
Test<ClassFinder.ClassInfo> test = getActionClassTest();
for (Class<?> clazz : finder.findClasses(test)) {
classes.add(clazz);
}
}
} catch (Exception ex) {
if (LOG.isErrorEnabled())
LOG.error("Unable to scan named packages", ex);
}
return classes;
}
protected boolean isReloadEnabled() {
return devMode && reload;
}
protected void initReloadClassLoader() {
// when the configuration is reloaded, a new classloader will be setup
if (isReloadEnabled() && reloadingClassLoader == null)
reloadingClassLoader = new ReloadingClassLoader(getClassLoader());
}
protected ClassLoaderInterface getClassLoaderInterface() {
if (isReloadEnabled())
return new ClassLoaderInterfaceDelegate(this.reloadingClassLoader);
else {
/*
* if there is a ClassLoaderInterface in the context, use it,
* otherwise default to the default ClassLoaderInterface (a wrapper
* around the current thread classloader) using this, other plugins
* (like OSGi) can plugin their own classloader for a while and it
* will be used by Convention (it cannot be a bean, as Convention is
* likely to be called multiple times, and it needs to use the
* default ClassLoaderInterface during normal startup)
*/
ClassLoaderInterface classLoaderInterface = null;
ActionContext ctx = ActionContext.getContext();
if (ctx != null)
classLoaderInterface = (ClassLoaderInterface) ctx
.get(ClassLoaderInterface.CLASS_LOADER_INTERFACE);
return (ClassLoaderInterface) ObjectUtils.defaultIfNull(
classLoaderInterface, new ClassLoaderInterfaceDelegate(
getClassLoader()));
}
}
protected ClassLoader getClassLoader() {
return Thread.currentThread().getContextClassLoader();
}
private UrlSet buildUrlSet() throws IOException {
ClassLoaderInterface classLoaderInterface = getClassLoaderInterface();
UrlSet urlSet = new UrlSet(fileManager, classLoaderInterface, this.fileProtocols);
//excluding the urls found by the parent class loader is desired, but fails in JBoss (all urls are removed)
if (excludeParentClassLoader) {
//exclude parent of classloaders
ClassLoaderInterface parent = classLoaderInterface.getParent();
//if reload is enabled, we need to step up one level, otherwise the UrlSet will be empty
//this happens because the parent of the realoding class loader is the web app classloader
if (parent != null && isReloadEnabled())
parent = parent.getParent();
if (parent != null)
urlSet = urlSet.exclude(parent);
try {
// This may fail in some sandboxes, ie GAE
ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader();
urlSet = urlSet.exclude(new ClassLoaderInterfaceDelegate(systemClassLoader.getParent()));
} catch (SecurityException e) {
if (LOG.isWarnEnabled())
LOG.warn("Could not get the system classloader due to security constraints, there may be improper urls left to scan");
}
}
//try to find classes dirs inside war files
urlSet = urlSet.includeClassesUrl(classLoaderInterface);
urlSet = urlSet.excludeJavaExtDirs();
urlSet = urlSet.excludeJavaEndorsedDirs();
try {
urlSet = urlSet.excludeJavaHome();
} catch (NullPointerException e) {
// This happens in GAE since the sandbox contains no java.home directory
if (LOG.isWarnEnabled())
LOG.warn("Could not exclude JAVA_HOME, is this a sandbox jvm?");
}
urlSet = urlSet.excludePaths(System.getProperty("sun.boot.class.path", ""));
urlSet = urlSet.exclude(".*/JavaVM.framework/.*");
if (includeJars == null) {
urlSet = urlSet.exclude(".*?\\.jar(!/|/)?");
} else {
//jar urls regexes were specified
List<URL> rawIncludedUrls = urlSet.getUrls();
Set<URL> includeUrls = new HashSet<URL>();
boolean[] patternUsed = new boolean[includeJars.length];
for (URL url : rawIncludedUrls) {
if (fileProtocols.contains(url.getProtocol())) {
//it is a jar file, make sure it macthes at least a url regex
for (int i = 0; i < includeJars.length; i++) {
String includeJar = includeJars[i];
if (Pattern.matches(includeJar, url.toExternalForm())) {
includeUrls.add(url);
patternUsed[i] = true;
break;
}
}
} else {
//it is not a jar
includeUrls.add(url);
}
}
if (LOG.isWarnEnabled()) {
for (int i = 0; i < patternUsed.length; i++) {
if (!patternUsed[i]) {
LOG.warn("The includeJars pattern [#0] did not match any jars in the classpath", includeJars[i]);
}
}
}
return new UrlSet(fileManager, includeUrls);
}
return urlSet;
}
public static boolean contains(String[] strings, String value,
boolean ignoreCase) {
if (strings != null) {
for (String string : strings) {
if ((string.equals(value))
|| ((ignoreCase) && (string.equalsIgnoreCase(value)))) {
return true;
}
}
}
return false;
}
}