Generified Flow Search Algorithms

.gitignore

@@ -1,4 +1,28 @@
 target
 work
-.idea
+
+# IntelliJ project files 
 *.iml
+*.iws
+*.ipr
+.idea
+out
+
+# eclipse project file
+.settings
+.classpath
+.project
+build
+
+# vim
+*~
+*.swp
+
+# ctags
+tags
+
+# OS X
+.DS_Store
+
+# mvn versions:set
+pom.xml.versionsBackup

pom.xml

@@ -33,7 +33,7 @@
     </parent>
     <groupId>org.jenkins-ci.plugins.workflow</groupId>
     <artifactId>workflow-api</artifactId>
-    <version>2.2-SNAPSHOT</version>
+    <version>2.2-blockapis-SNAPSHOT</version>
     <packaging>hpi</packaging>
     <name>Pipeline: API</name>
     <url>https://wiki.jenkins-ci.org/display/JENKINS/Pipeline+API+Plugin</url>
@@ -48,7 +48,7 @@
         <developerConnection>scm:git:git@github.com:jenkinsci/${project.artifactId}-plugin.git</developerConnection>
         <url>https://github.com/jenkinsci/${project.artifactId}-plugin</url>
       <tag>HEAD</tag>
-  </scm>
+    </scm>
     <repositories>
         <repository>
             <id>repo.jenkins-ci.org</id>
@@ -70,5 +70,23 @@
             <artifactId>workflow-step-api</artifactId>
             <version>1.15</version>
         </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>workflow-job</artifactId>
+            <version>1.15</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>workflow-cps</artifactId>
+            <version>2.2</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>workflow-basic-steps</artifactId>
+            <version>1.15</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 </project>

src/main/java/org/jenkinsci/plugins/workflow/graph/FlowNode.java

@@ -114,13 +114,15 @@ public final boolean isRunning() {
     /**
      * Returns a read-only view of parents.
      */
+    @Nonnull
     public List<FlowNode> getParents() {
         if (parents == null) {
             parents = loadParents(parentIds);
         }
         return parents;
     }
 
+    @Nonnull
     private List<FlowNode> loadParents(List<String> parentIds) {
         List<FlowNode> _parents = new ArrayList<FlowNode>(parentIds.size());
         for (String parentId : parentIds) {
@@ -135,6 +137,7 @@ private List<FlowNode> loadParents(List<String> parentIds) {
 
     @Restricted(DoNotUse.class)
     @Exported(name="parents")
+    @Nonnull
     public List<String> getParentIds() {
         List<String> ids = new ArrayList<String>(2);
         for (FlowNode parent : getParents()) {