Merge pull request #3310 from oowekyala:update-ExceptionAsFlowControl

[java] Update rule ExceptionAsFlowControl #3310

.ci/files/all-java.xml

@@ -134,7 +134,7 @@
     <rule ref="category/java/design.xml/CyclomaticComplexity"/>
     <rule ref="category/java/design.xml/DataClass"/>
     <rule ref="category/java/design.xml/DoNotExtendJavaLangError"/>
-    <!-- <rule ref="category/java/design.xml/ExceptionAsFlowControl"/> -->
+    <rule ref="category/java/design.xml/ExceptionAsFlowControl"/>
     <rule ref="category/java/design.xml/ExcessiveClassLength"/>
     <rule ref="category/java/design.xml/ExcessiveImports"/>
     <rule ref="category/java/design.xml/ExcessiveMethodLength"/>

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/design/ExceptionAsFlowControlRule.java

@@ -6,7 +6,6 @@ package net.sourceforge.pmd.lang.java.rule.design;
 
 import net.sourceforge.pmd.lang.ast.NodeStream;
 import net.sourceforge.pmd.lang.java.ast.ASTCatchClause;
-import net.sourceforge.pmd.lang.java.ast.ASTCatchParameter;
 import net.sourceforge.pmd.lang.java.ast.ASTThrowStatement;
 import net.sourceforge.pmd.lang.java.ast.ASTTryStatement;
 import net.sourceforge.pmd.lang.java.ast.JavaNode;
@@ -41,8 +40,8 @@ public class ExceptionAsFlowControlRule extends AbstractJavaRule {
 
         enclosingTries.flatMap(ASTTryStatement::getCatchClauses)
                       .map(ASTCatchClause::getParameter)
-                      .flatMap(ASTCatchParameter::getAllExceptionTypes)
-                      .filter(ex -> ex.getTypeMirror().isSubtypeOf(thrownType))
+                      .filter(exParam -> exParam.getAllExceptionTypes().any(type -> thrownType.isSubtypeOf(type.getTypeMirror())))
+                      .take(1)
                       .forEach(ex -> addViolation(data, ex));
         return data;
     }

pmd-java/src/test/java/net/sourceforge/pmd/lang/java/rule/design/ExceptionAsFlowControlTest.java

@@ -6,7 +6,6 @@ package net.sourceforge.pmd.lang.java.rule.design;
 
 import net.sourceforge.pmd.testframework.PmdRuleTst;
 
-@org.junit.Ignore("Rule has not been updated yet")
 public class ExceptionAsFlowControlTest extends PmdRuleTst {
     // no additional unit tests
 }

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/design/xml/ExceptionAsFlowControl.xml

@@ -21,6 +21,7 @@ public class Foo {
         }
     }
 }
+class WrapperException extends Exception {}
         ]]></code>
     </test-code>
 
@@ -40,12 +41,13 @@ public class Foo {
         <description>BUG 996007</description>
         <expected-problems>0</expected-problems>
         <code><![CDATA[
+import java.io.IOException;
 public class Foo {
-    void bar() {
+    void bar(Foo foo) {
         try {
         } catch (IOException e) {
             if (foo!=null)
-                throw new IOException(foo.getResponseMessage());
+                throw new IOException(foo.toString());
             else
                 throw e;
         }
@@ -68,4 +70,28 @@ public class Foo {
 }
         ]]></code>
     </test-code>
+    <test-code>
+        <description>Catch block for subtype</description>
+        <expected-problems>1</expected-problems>
+        <expected-linenumbers>11</expected-linenumbers>
+        <code><![CDATA[
+public class Foo {{
+
+    try {
+        throw new TopE();
+    } catch (SubE e) { // no violation
+
+    }
+
+    try {
+        throw new SubE();
+    } catch (TopE e) { // warn
+
+    }
+}}
+class TopE extends Exception { }
+class SubE extends TopE { }
+
+        ]]></code>
+    </test-code>
 </test-data>