WW-5289 Fixes creating executor to avoid locking JVM on shutdown

apps/showcase/src/main/resources/struts-wait.xml

@@ -25,7 +25,10 @@
 
 <struts>
 
-    <bean type="org.apache.struts2.interceptor.exec.ExecutorProvider" class="org.apache.struts2.showcase.wait.ThreadPoolExecutorProvider"/>
+    <bean type="org.apache.struts2.interceptor.exec.ExecutorProvider" name="threadPool"
+          class="org.apache.struts2.showcase.wait.ThreadPoolExecutorProvider"/>
+
+    <constant name="struts.executor.provider" value="threadPool"/>
 
     <package name="wait" extends="struts-default" namespace="/wait">
         <default-action-ref name="index"/>

core/src/main/java/com/opensymphony/xwork2/config/providers/StrutsDefaultConfigurationProvider.java

@@ -118,6 +118,8 @@ import org.apache.struts2.conversion.StrutsTypeConverterCreator;
 import org.apache.struts2.conversion.StrutsTypeConverterHolder;
 import org.apache.struts2.dispatcher.HttpParameters;
 import org.apache.struts2.dispatcher.Parameter;
+import org.apache.struts2.interceptor.exec.ExecutorProvider;
+import org.apache.struts2.interceptor.exec.StrutsExecutorProvider;
 import org.apache.struts2.url.QueryStringBuilder;
 import org.apache.struts2.url.QueryStringParser;
 import org.apache.struts2.url.StrutsQueryStringBuilder;
@@ -242,6 +244,8 @@ public class StrutsDefaultConfigurationProvider implements ConfigurationProvider
             .factory(QueryStringParser.class, StrutsQueryStringParser.class, Scope.SINGLETON)
             .factory(UrlEncoder.class, StrutsUrlEncoder.class, Scope.SINGLETON)
             .factory(UrlDecoder.class, StrutsUrlDecoder.class, Scope.SINGLETON)
+
+            .factory(ExecutorProvider.class, StrutsExecutorProvider.class, Scope.SINGLETON)
         ;
 
         props.setProperty(StrutsConstants.STRUTS_ENABLE_DYNAMIC_METHOD_INVOCATION, Boolean.FALSE.toString());

core/src/main/java/org/apache/struts2/StrutsConstants.java

@@ -463,4 +463,7 @@ public final class StrutsConstants {
 
     /** A global flag to set property {@link org.apache.struts2.components.Checkbox#setSubmitUnchecked(String)} */
     public static final String STRUTS_UI_CHECKBOX_SUBMIT_UNCHECKED = "struts.ui.checkbox.submitUnchecked";
+
+    /** See {@link org.apache.struts2.interceptor.exec.ExecutorProvider} */
+    public static final String STRUTS_EXECUTOR_PROVIDER = "struts.executor.provider";
 }

core/src/main/java/org/apache/struts2/config/StrutsBeanSelectionProvider.java

@@ -66,6 +66,7 @@ import org.apache.struts2.dispatcher.DispatcherErrorHandler;
 import org.apache.struts2.dispatcher.StaticContentLoader;
 import org.apache.struts2.dispatcher.mapper.ActionMapper;
 import org.apache.struts2.dispatcher.multipart.MultiPartRequest;
+import org.apache.struts2.interceptor.exec.ExecutorProvider;
 import org.apache.struts2.url.QueryStringBuilder;
 import org.apache.struts2.url.QueryStringParser;
 import org.apache.struts2.url.UrlDecoder;
@@ -438,6 +439,8 @@ public class StrutsBeanSelectionProvider extends AbstractBeanSelectionProvider {
         alias(UrlEncoder.class, StrutsConstants.STRUTS_URL_ENCODER, builder, props, Scope.SINGLETON);
         alias(UrlDecoder.class, StrutsConstants.STRUTS_URL_DECODER, builder, props, Scope.SINGLETON);
 
+        alias(ExecutorProvider.class, StrutsConstants.STRUTS_EXECUTOR_PROVIDER, builder, props, Scope.SINGLETON);
+
         switchDevMode(props);
     }
 

core/src/main/java/org/apache/struts2/interceptor/ExecuteAndWaitInterceptor.java

@@ -197,7 +197,7 @@ public class ExecuteAndWaitInterceptor extends MethodFilterInterceptor {
         this.container = container;
     }
 
-    @Inject(required = false)
+    @Inject
     public void setExecutorProvider(ExecutorProvider executorProvider) {
         this.executor = executorProvider;
     }
@@ -387,7 +387,8 @@ public class ExecuteAndWaitInterceptor extends MethodFilterInterceptor {
     public void init() {
         super.init();
         if (executor == null) {
-            executor = new StrutsExecutorProvider();
+            LOG.debug("Using: {} as ExecutorProvider", StrutsExecutorProvider.class.getSimpleName());
+            executor = container.getInstance(StrutsExecutorProvider.class);
         }
     }
 

core/src/main/java/org/apache/struts2/interceptor/exec/StrutsExecutorProvider.java

@@ -31,7 +31,7 @@ public class StrutsExecutorProvider implements ExecutorProvider {
     private final ExecutorService executor;
 
     public StrutsExecutorProvider() {
-        this.executor = Executors.newSingleThreadExecutor();
+        this.executor = Executors.newFixedThreadPool(2);
     }
 
     @Override

core/src/main/resources/struts-beans.xml

@@ -245,4 +245,7 @@
     <bean type="org.apache.struts2.url.UrlDecoder" name="strutsUrlDecoder"
           class="org.apache.struts2.url.StrutsUrlDecoder" scope="singleton"/>
 
+    <bean type="org.apache.struts2.interceptor.exec.ExecutorProvider" name="struts"
+          class="org.apache.struts2.interceptor.exec.StrutsExecutorProvider"/>
+
 </struts>