RAT-566: fix some spotbugs issues in core (#688)

* fixed spotbugs issues

* added exception tests

* added license headers

Author: Claudenw

apache-rat-core/src/main/java/org/apache/rat/ConfigurationException.java

@@ -26,8 +26,8 @@ public class ConfigurationException extends RuntimeException {
     private static final long serialVersionUID = 7257245932787579431L;
 
     public static ConfigurationException from(final Exception e) {
-        if (e instanceof ConfigurationException) {
-            return (ConfigurationException) e;
+        if (e instanceof ConfigurationException exists) {
+            return exists;
         }
         return new ConfigurationException(e);
     }

apache-rat-core/src/main/java/org/apache/rat/Defaults.java

@@ -49,7 +49,8 @@ public final class Defaults {
     /** The default configuration file from the package. */
     private static final URI DEFAULT_CONFIG_URI;
     /** The path to the default configuration file. */
-    private static final String DEFAULT_CONFIG_PATH = "/org/apache/rat/default.xml";
+    // sonar wants this to be configurable.
+    private static final String DEFAULT_CONFIG_PATH = "/org/apache/rat/default.xml"; // NOSONAR
     /** The default ARCHIVES processing style. */
     public static final ReportConfiguration.Processing ARCHIVE_PROCESSING = ReportConfiguration.Processing.NOTIFICATION;
     /** The default STANDARD processing style. */

apache-rat-core/src/main/java/org/apache/rat/ImplementationException.java

@@ -26,8 +26,8 @@ public class ImplementationException extends RuntimeException {
     private static final long serialVersionUID = 7257245932787579431L;
 
     public static ImplementationException makeInstance(final Exception e) {
-        if (e instanceof ImplementationException) {
-            return (ImplementationException) e;
+        if (e instanceof ImplementationException exists) {
+            return exists;
         }
         return new ImplementationException(e);
     }

apache-rat-core/src/main/java/org/apache/rat/analysis/license/SimplePatternBasedLicense.java

@@ -20,6 +20,7 @@
 
 import java.util.Arrays;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.apache.rat.DeprecationReporter;
 import org.apache.rat.configuration.builders.AbstractBuilder;
 import org.apache.rat.configuration.builders.AnyBuilder;
@@ -31,6 +32,7 @@
  * @since Rat 0.8
  * @deprecated Use new configuration options
  */
+@SuppressFBWarnings("EI_EXPOSE_REP2")
 @Deprecated // Since 0.16
 @DeprecationReporter.Info(since = "0.16", forRemoval = true, use = "new configuration options")
 public class SimplePatternBasedLicense  extends BaseLicense {

apache-rat-core/src/main/java/org/apache/rat/analysis/matchers/SimpleTextMatcher.java

@@ -23,6 +23,8 @@
 import org.apache.rat.config.parameters.ComponentType;
 import org.apache.rat.config.parameters.ConfigComponent;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
 /**
  * A simple text matching IHeaderMatcher implementation.
  */
@@ -44,11 +46,12 @@ public SimpleTextMatcher(final String simpleText) {
         this(null, simpleText);
     }
 
+    // no sonar and supress FI_USELESS because this is how we ensure that the finalize bug does not bite us
+    @SuppressFBWarnings("FI_USELESS")
     @Override
     protected final void finalize() throws Throwable { // NOSONAR
-        // no sonar because this is how we ensure that the finalize bug does not bite us
+        // finalizer attack remediation.
         super.finalize(); // NOSONAR
-      // finalizer attack remediation.
     }
 
     /**

apache-rat-core/src/main/java/org/apache/rat/configuration/builders/MatcherRefBuilder.java

@@ -27,6 +27,8 @@
 import org.apache.rat.config.parameters.ConfigComponent;
 import org.apache.rat.config.parameters.MatcherBuilder;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
 /**
  * A reference matching Matcher builder.
  * <p>
@@ -62,6 +64,7 @@ public MatcherRefBuilder setRefId(final String refId) {
      * @param matchers the Map of ids to instances.
      * @return this builder for chaining.
      */
+    @SuppressFBWarnings(value = "EI_EXPOSE_REP2", justification = "Expected external update of matchers.")
     public MatcherRefBuilder setMatcherMap(final Map<String, IHeaderMatcher> matchers) {
         // this method is called by reflection
         this.matchers = matchers;
@@ -109,6 +112,7 @@ public static class IHeaderMatcherProxy implements IHeaderMatcher {
          * @param proxyId the id of the matcher to find.
          * @param matchers a mapping of matchers that have been found.
          */
+        @SuppressFBWarnings(value = "EI_EXPOSE_REP2", justification = "Expected external update of matchers.")
         public IHeaderMatcherProxy(final String proxyId, final Map<String, IHeaderMatcher> matchers) {
             this.proxyId = proxyId;
             this.matchers = matchers;

apache-rat-core/src/main/java/org/apache/rat/header/HeaderMatcher.java

@@ -18,6 +18,7 @@
  */ 
 package org.apache.rat.header;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.apache.rat.DeprecationReporter;
 
 import java.io.IOException;
@@ -35,6 +36,7 @@
  * <p><strong>Note:</strong> use only from a single thread.</p>
  *
  */
+@SuppressFBWarnings("EI_EXPOSE_REP2")
 @Deprecated // since 0.17
 @DeprecationReporter.Info(since = "0.17", forRemoval = true)
 public class HeaderMatcher {

apache-rat-core/src/main/java/org/apache/rat/help/Licenses.java

@@ -43,6 +43,8 @@
 import org.apache.rat.license.ILicenseFamily;
 import org.apache.rat.license.LicenseSetFactory.LicenseFilter;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
 import static java.lang.String.format;
 
 /**
@@ -64,6 +66,7 @@ public final class Licenses extends AbstractHelp {
      * @param config The configuration that contains the license information.
      * @param writer the writer to write the report to.
      */
+    @SuppressFBWarnings("EI_EXPOSE_REP2")
     public Licenses(final ReportConfiguration config, final Writer writer) {
         this.config = config;
         this.licenses = config.getLicenses(LicenseFilter.ALL);

apache-rat-core/src/test/java/org/apache/rat/ConfigurationExceptionTest.java

@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one   *
+ * or more contributor license agreements.  See the NOTICE file *
+ * distributed with this work for additional information        *
+ * regarding copyright ownership.  The ASF licenses this file   *
+ * to you under the Apache License, Version 2.0 (the            *
+ * "License"); you may not use this file except in compliance   *
+ * with the License.  You may obtain a copy of the License at   *
+ *                                                              *
+ *   https://www.apache.org/licenses/LICENSE-2.0                 *
+ *                                                              *
+ * Unless required by applicable law or agreed to in writing,   *
+ * software distributed under the License is distributed on an  *
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
+ * KIND, either express or implied.  See the License for the    *
+ * specific language governing permissions and limitations      *
+ * under the License.                                           *
+ */
+package org.apache.rat;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ConfigurationExceptionTest {
+
+    @Test
+    void fromTest() {
+        RuntimeException runTime = new RuntimeException();
+        assertThat(ConfigurationException.from(runTime))
+                .isInstanceOf(ConfigurationException.class)
+                .hasCause(runTime);
+
+        Exception ex = new Exception();
+        assertThat(ConfigurationException.from(ex))
+                .isInstanceOf(ConfigurationException.class)
+                .hasCause(ex);
+
+        ex = new ConfigurationException("yee haw");
+        assertThat(ConfigurationException.from(ex))
+                .isInstanceOf(ConfigurationException.class)
+                .isEqualTo(ex);
+    }
+}

apache-rat-core/src/test/java/org/apache/rat/ImplementationExceptionTest.java

@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one   *
+ * or more contributor license agreements.  See the NOTICE file *
+ * distributed with this work for additional information        *
+ * regarding copyright ownership.  The ASF licenses this file   *
+ * to you under the Apache License, Version 2.0 (the            *
+ * "License"); you may not use this file except in compliance   *
+ * with the License.  You may obtain a copy of the License at   *
+ *                                                              *
+ *   https://www.apache.org/licenses/LICENSE-2.0                 *
+ *                                                              *
+ * Unless required by applicable law or agreed to in writing,   *
+ * software distributed under the License is distributed on an  *
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
+ * KIND, either express or implied.  See the License for the    *
+ * specific language governing permissions and limitations      *
+ * under the License.                                           *
+ */
+package org.apache.rat;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ImplementationExceptionTest {
+
+    @Test
+    void fromTest() {
+        RuntimeException runTime = new RuntimeException();
+        assertThat(ImplementationException.makeInstance(runTime))
+                .isInstanceOf(ImplementationException.class)
+                .hasCause(runTime);
+
+        Exception ex = new Exception();
+        assertThat(ImplementationException.makeInstance(ex))
+                .isInstanceOf(ImplementationException.class)
+                .hasCause(ex);
+
+        ex = new ImplementationException("yee haw");
+        assertThat(ImplementationException.makeInstance(ex))
+                .isInstanceOf(ImplementationException.class)
+                .isEqualTo(ex);
+    }
+}