[java] CloseResource: fix false positive with close on not closeable

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/errorprone/CloseResourceRule.java

@@ -623,7 +623,7 @@ public class CloseResourceRule extends AbstractJavaRule {
     @Override
     public Object visit(ASTPrimaryPrefix prefix, Object data) {
         ASTName methodCall = prefix.getFirstChildOfType(ASTName.class);
-        if (methodCall != null) {
+        if (methodCall != null && isNodeInstanceOfResourceType(methodCall)) {
             String closedVar = getVariableClosedByMethodCall(methodCall);
             if (closedVar != null && isNotInFinallyBlock(prefix) && !reportedVarNames.contains(closedVar)) {
                 String violationMsg = closeInFinallyBlockMessageForVar(closedVar);

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/errorprone/xml/CloseResource.xml

@@ -1363,6 +1363,25 @@ public class Foo {
             int d = ois.read();
         }
     }
+}
+        ]]></code>
+    </test-code>
+
+    <test-code>
+        <description>false positive with close on not closeable</description>
+        <expected-problems>0</expected-problems>
+        <code><![CDATA[
+import java.io.*;
+import com.google.common.io.Closeables;
+import com.google.common.io.Flushables;
+
+public class Foo {
+    private static void flushAndCloseOutStream(OutputStream stream) throws IOException {
+        if (stream != null) {
+            Flushables.flush(stream, false);
+        }
+        Closeables.close(stream, false);
+    }
 }
         ]]></code>
     </test-code>