From 5deaab78190dd98df1fd6b2ee2ebbdec9711224b Mon Sep 17 00:00:00 2001
From: Sergey Evdokimov <sergey.evdokimov@jetbrains.com>
Date: Wed, 18 Apr 2012 18:08:06 +0400
Subject: [PATCH] IDEA-84800 strange and unhelpful "value must not be empty" in
 the pom.xml

---
 .../dom/MavenPluginConfigurationDomExtender.java   | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/plugins/maven/src/main/java/org/jetbrains/idea/maven/dom/MavenPluginConfigurationDomExtender.java b/plugins/maven/src/main/java/org/jetbrains/idea/maven/dom/MavenPluginConfigurationDomExtender.java
index eebd3737476a..54a34342c885 100644
--- a/plugins/maven/src/main/java/org/jetbrains/idea/maven/dom/MavenPluginConfigurationDomExtender.java
+++ b/plugins/maven/src/main/java/org/jetbrains/idea/maven/dom/MavenPluginConfigurationDomExtender.java
@@ -15,6 +15,7 @@
  */
 package org.jetbrains.idea.maven.dom;
 
+import com.google.common.collect.ImmutableSet;
 import com.intellij.openapi.util.Key;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.PsiElement;
@@ -41,14 +42,15 @@ import org.jetbrains.idea.maven.dom.plugin.MavenDomParameter;
 import org.jetbrains.idea.maven.dom.plugin.MavenDomPluginModel;
 
 import java.lang.annotation.Annotation;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 public class MavenPluginConfigurationDomExtender extends DomExtender<MavenDomConfiguration> {
   public static final Key<ParameterData> PLUGIN_PARAMETER_KEY = Key.create("MavenPluginConfigurationDomExtender.PLUGIN_PARAMETER_KEY");
 
+  private static final Set<String> COLLECTIONS_TYPE_NAMES = ImmutableSet.of("java.util.Collection", "java.util.Set", "java.util.List",
+                                                                            "java.util.ArrayList", "java.util.HashSet",
+                                                                            "java.util.LinkedList");
+
   @Override
   public void registerExtensions(@NotNull MavenDomConfiguration config, @NotNull DomExtensionsRegistrar r) {
     MavenDomPluginModel pluginModel = MavenPluginDomUtil.getMavenPluginModel(config);
@@ -226,9 +228,9 @@ public class MavenPluginConfigurationDomExtender extends DomExtender<MavenDomCon
 
   private static boolean isCollection(MavenDomParameter parameter) {
     String type = parameter.getType().getStringValue();
-    if (type.endsWith("[]")) return true;
+    if (type == null) return false;
 
-    return type.equals("java.util.List") || type.equals("java.util.Set") || type.equals("java.util.Collection");
+    return type.endsWith("[]") || COLLECTIONS_TYPE_NAMES.contains(type);
   }
 
   public static class ParameterData {