Issue #3617: make FinalLocalVariable not check multi-catch vars

src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheck.java

@@ -195,7 +195,8 @@ public class FinalLocalVariableCheck extends AbstractCheck {
                 if (!isInLambda(ast)
                         && !ast.branchContains(TokenTypes.FINAL)
                         && !isInAbstractOrNativeMethod(ast)
-                        && !ScopeUtils.isInInterfaceBlock(ast)) {
+                        && !ScopeUtils.isInInterfaceBlock(ast)
+                        && !isMultipleTypeCatch(ast)) {
                     insertParameter(ast);
                 }
                 break;
@@ -468,6 +469,16 @@ public class FinalLocalVariableCheck extends AbstractCheck {
         }
     }
 
+    /**
+     * Check if given parameter definition is a multiple type catch.
+     * @param parameterDefAst parameter definition
+     * @return true if it is a multiple type catch, false otherwise
+     */
+    private boolean isMultipleTypeCatch(DetailAST parameterDefAst) {
+        final DetailAST typeAst = parameterDefAst.findFirstToken(TokenTypes.TYPE);
+        return typeAst.getFirstChild().getType() == TokenTypes.BOR;
+    }
+
     /**
      * Whether the final variable candidate should be removed from the list of final local variable
      * candidates.

src/test/java/com/puppycrawl/tools/checkstyle/checks/coding/FinalLocalVariableCheckTest.java

@@ -239,4 +239,13 @@ public class FinalLocalVariableCheckTest
         verify(checkConfig, getPath("InputFinalLocalVariableMultipleAndNestedConditions.java"),
             expected);
     }
+
+    @Test
+    public void testMultiTypeCatch() throws Exception {
+        final DefaultConfiguration checkConfig = createCheckConfig(FinalLocalVariableCheck.class);
+        checkConfig.addAttribute("tokens", "PARAMETER_DEF,VARIABLE_DEF");
+        final String[] expected = CommonUtils.EMPTY_STRING_ARRAY;
+        verify(checkConfig, getPath("InputFinalLocalVariableMultiCatch.java"),
+                expected);
+    }
 }

src/test/resources/com/puppycrawl/tools/checkstyle/checks/coding/InputFinalLocalVariableMultiCatch.java

@@ -0,0 +1,13 @@
+package com.puppycrawl.tools.checkstyle.checks.coding;
+
+public class InputFinalLocalVariableMultiCatch {
+    public void demo() throws Throwable {
+        try {
+            // do nothing
+        } catch (final NumberFormatException ex) {
+            // do nothing
+        } catch (IllegalStateException | NullPointerException ex) {
+            // do nothing
+        }
+    }
+}