Merge pull request #29 Enable checkstyle

build.gradle

@@ -3,6 +3,7 @@ plugins {
     id 'maven-publish'
     id 'signing'
     id("io.github.gradle-nexus.publish-plugin") version "1.1.0"
+    id 'checkstyle'
 }
 
 group = 'ch.geowerkstatt.ilivalidator.extensions.functions'
@@ -53,7 +54,7 @@ publishing {
                 developers {
                     developer {
                         id = 'GeoWerkstatt'
-                        name = 'GeoWerkstatt GmbHH'
+                        name = 'GeoWerkstatt GmbH'
                         email = '[email protected]'
                     }
                 }

config/checkstyle/checkstyle.xml

@@ -0,0 +1,207 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+          "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+          "https://checkstyle.org/dtds/configuration_1_3.dtd">
+
+<!--
+
+  Checkstyle configuration that checks the sun coding conventions from:
+
+    - the Java Language Specification at
+      https://docs.oracle.com/javase/specs/jls/se11/html/index.html
+
+    - the Sun Code Conventions at https://www.oracle.com/java/technologies/javase/codeconventions-contents.html
+
+    - the Javadoc guidelines at
+      https://www.oracle.com/technical-resources/articles/java/javadoc-tool.html
+
+    - the JDK Api documentation https://docs.oracle.com/en/java/javase/11/
+
+    - some best practices
+
+  Checkstyle is very configurable. Be sure to read the documentation at
+  https://checkstyle.org (or in your downloaded distribution).
+
+  Most Checks are configurable, be sure to consult the documentation.
+
+  To completely disable a check, just comment it out or delete it from the file.
+  To suppress certain violations please review suppression filters.
+
+  Finally, it is worth reading the documentation.
+
+-->
+
+<module name="Checker">
+  <!--
+      If you set the basedir property below, then all reported file
+      names will be relative to the specified directory. See
+      https://checkstyle.org/config.html#Checker
+
+      <property name="basedir" value="${basedir}"/>
+  -->
+  <property name="severity" value="error"/>
+
+  <property name="fileExtensions" value="java, properties, xml"/>
+
+  <!-- Excludes all 'module-info.java' files              -->
+  <!-- See https://checkstyle.org/filefilters/index.html -->
+  <module name="BeforeExecutionExclusionFileFilter">
+    <property name="fileNamePattern" value="module\-info\.java$"/>
+  </module>
+
+  <!-- https://checkstyle.org/filters/suppressionfilter.html -->
+  <module name="SuppressionFilter">
+    <property name="file" value="${config_loc}/suppressions.xml"/>
+    <property name="optional" value="true"/>
+  </module>
+
+  <!-- Checks that a package-info.java file exists for each package.     -->
+  <!-- See https://checkstyle.org/checks/javadoc/javadocpackage.html#JavadocPackage -->
+  <!-- <module name="JavadocPackage"/> -->
+
+  <!-- Checks whether files end with a new line.                        -->
+  <!-- See https://checkstyle.org/checks/misc/newlineatendoffile.html -->
+  <module name="NewlineAtEndOfFile"/>
+
+  <!-- Checks that property files contain the same keys.         -->
+  <!-- See https://checkstyle.org/checks/misc/translation.html -->
+  <module name="Translation"/>
+
+  <!-- Checks for Size Violations.                    -->
+  <!-- See https://checkstyle.org/checks/sizes/index.html -->
+  <module name="FileLength"/>
+  <module name="LineLength">
+    <property name="fileExtensions" value="java"/>
+    <property name="max" value="200"/>
+  </module>
+
+  <!-- Checks for whitespace                               -->
+  <!-- See https://checkstyle.org/checks/whitespace/index.html -->
+  <module name="FileTabCharacter"/>
+
+  <!-- Miscellaneous other checks.                   -->
+  <!-- See https://checkstyle.org/checks/misc/index.html -->
+  <module name="RegexpSingleline">
+    <property name="format" value="\s+$"/>
+    <property name="minimum" value="0"/>
+    <property name="maximum" value="0"/>
+    <property name="message" value="Line has trailing spaces."/>
+  </module>
+
+  <!-- Checks for Headers                                -->
+  <!-- See https://checkstyle.org/checks/header/index.html   -->
+  <!-- <module name="Header"> -->
+  <!--   <property name="headerFile" value="${checkstyle.header.file}"/> -->
+  <!--   <property name="fileExtensions" value="java"/> -->
+  <!-- </module> -->
+
+  <module name="TreeWalker">
+
+    <!-- Checks for Javadoc comments.                     -->
+    <!-- See https://checkstyle.org/checks/javadoc/index.html -->
+    <module name="InvalidJavadocPosition"/>
+    <module name="JavadocMethod">
+      <property name="allowMissingParamTags" value="true"/>
+      <property name="allowMissingReturnTag" value="true"/>
+    </module>
+    <module name="JavadocType"/>
+    <module name="JavadocVariable">
+      <property name="scope" value="public"/>
+    </module>
+    <module name="JavadocStyle"/>
+    <module name="MissingJavadocMethod"/>
+
+    <!-- Checks for Naming Conventions.                  -->
+    <!-- See https://checkstyle.org/checks/naming/index.html -->
+    <module name="ConstantName"/>
+    <module name="LocalFinalVariableName"/>
+    <module name="LocalVariableName"/>
+    <module name="MemberName"/>
+    <module name="MethodName"/>
+    <module name="PackageName"/>
+    <module name="ParameterName"/>
+    <module name="StaticVariableName"/>
+    <module name="TypeName"/>
+
+    <!-- Checks for imports                              -->
+    <!-- See https://checkstyle.org/checks/imports/index.html -->
+    <module name="AvoidStarImport">
+      <property name="excludes" value="java.util"/>
+    </module>
+    <module name="IllegalImport"/> <!-- defaults to sun.* packages -->
+    <module name="RedundantImport"/>
+    <module name="UnusedImports">
+      <property name="processJavadoc" value="false"/>
+    </module>
+
+    <!-- Checks for Size Violations.                    -->
+    <!-- See https://checkstyle.org/checks/sizes/index.html -->
+    <module name="MethodLength"/>
+    <module name="ParameterNumber"/>
+
+    <!-- Checks for whitespace                               -->
+    <!-- See https://checkstyle.org/checks/whitespace/index.html -->
+    <module name="EmptyForIteratorPad"/>
+    <module name="GenericWhitespace"/>
+    <module name="MethodParamPad"/>
+    <module name="NoWhitespaceAfter"/>
+    <module name="NoWhitespaceBefore"/>
+    <module name="OperatorWrap"/>
+    <module name="ParenPad"/>
+    <module name="TypecastParenPad"/>
+    <module name="WhitespaceAfter"/>
+    <module name="WhitespaceAround"/>
+
+    <!-- Modifier Checks                                    -->
+    <!-- See https://checkstyle.org/checks/modifier/index.html -->
+    <module name="ModifierOrder"/>
+    <module name="RedundantModifier"/>
+
+    <!-- Checks for blocks. You know, those {}'s         -->
+    <!-- See https://checkstyle.org/checks/blocks/index.html -->
+    <module name="AvoidNestedBlocks"/>
+    <module name="EmptyBlock"/>
+    <module name="LeftCurly"/>
+    <module name="NeedBraces"/>
+    <module name="RightCurly"/>
+
+    <!-- Checks for common coding problems               -->
+    <!-- See https://checkstyle.org/checks/coding/index.html -->
+    <module name="EmptyStatement"/>
+    <module name="EqualsHashCode"/>
+    <!-- <module name="HiddenField" /> -->
+    <module name="IllegalInstantiation"/>
+    <module name="InnerAssignment"/>
+    <!-- <module name="MagicNumber"/> -->
+    <module name="MissingSwitchDefault"/>
+    <module name="MultipleVariableDeclarations"/>
+    <module name="SimplifyBooleanExpression"/>
+    <module name="SimplifyBooleanReturn"/>
+
+    <!-- Checks for class design                         -->
+    <!-- See https://checkstyle.org/checks/design/index.html -->
+    <module name="DesignForExtension"/>
+    <module name="FinalClass"/>
+    <module name="HideUtilityClassConstructor"/>
+    <module name="InterfaceIsType"/>
+    <module name="VisibilityModifier">
+      <property name="protectedAllowed" value="true"/>
+    </module>
+
+    <!-- Miscellaneous other checks.                   -->
+    <!-- See https://checkstyle.org/checks/misc/index.html -->
+    <module name="ArrayTypeStyle"/>
+    <!-- <module name="FinalParameters"/> -->
+    <module name="TodoComment"/>
+    <module name="UpperEll"/>
+
+    <!-- https://checkstyle.org/filters/suppressionxpathfilter.html -->
+    <module name="SuppressionXpathFilter">
+      <property name="file" value="${org.checkstyle.sun.suppressionxpathfilter.config}"
+                default="checkstyle-xpath-suppressions.xml" />
+      <property name="optional" value="true"/>
+    </module>
+
+  </module>
+
+</module>

config/checkstyle/suppressions.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<!DOCTYPE suppressions PUBLIC
+        "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
+        "https://checkstyle.org/dtds/suppressions_1_2.dtd">
+
+<!-- https://checkstyle.org/filters/suppressionfilter.html -->
+<suppressions>
+
+    <!-- Disable some checks for test classes -->
+    <suppress checks="MissingJavadoc\w+Check|LineLengthCheck|VisibilityModifierCheck" files="[\\/]test[\\/]java[\\/]" />
+
+</suppressions>

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/BaseInterlisFunction.java

@@ -18,7 +18,7 @@ public abstract class BaseInterlisFunction implements InterlisFunction {
     protected Validator validator;
 
     @Override
-    public void init(TransferDescription td, Settings settings, IoxValidationConfig validationConfig, ObjectPool objectPool, LogEventFactory logEventFactory) {
+    public final void init(TransferDescription td, Settings settings, IoxValidationConfig validationConfig, ObjectPool objectPool, LogEventFactory logEventFactory) {
         this.logger = logEventFactory;
         this.logger.setValidationConfig(validationConfig);
         this.td = td;
@@ -27,10 +27,10 @@ public void init(TransferDescription td, Settings settings, IoxValidationConfig
     }
 
     @Override
-    public Value evaluate(String validationKind, String usageScope, IomObject mainObj, Value[] actualArguments) {
+    public final Value evaluate(String validationKind, String usageScope, IomObject mainObj, Value[] actualArguments) {
 
         for (Value arg : actualArguments) {
-            if (arg.skipEvaluation()){
+            if (arg.skipEvaluation()) {
                 return arg;
             }
         }

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/EvaluationHelper.java

@@ -16,7 +16,21 @@
 import java.util.Iterator;
 import java.util.function.Function;
 
-public class EvaluationHelper {
+public final class EvaluationHelper {
+
+    private EvaluationHelper() {
+        // Utility class
+    }
+
+    /**
+     * Parse the {@code argPath} into a {@link PathEl} array.
+     *
+     * @param validator the {@link Validator} instance.
+     * @param contextClass the {@link Viewable} definition where the {@code argPath} starts.
+     * @param argPath the path string to parse. see {@link Value#getValue()}.
+     *
+     * @return the parsed {@link PathEl} array or {@code null} if the {@code argPath} could not be parsed.
+     */
     public static PathEl[] getAttributePathEl(Validator validator, Viewable<Element> contextClass, Value argPath) {
         try {
             ObjectPath objectPath = validator.parseObjectOrAttributePath(contextClass, argPath.getValue());
@@ -29,6 +43,10 @@ public static PathEl[] getAttributePathEl(Validator validator, Viewable<Element>
         return null;
     }
 
+    /**
+     * Get the {@link Viewable} (e.g. the class definition) from the {@link TransferDescription}.
+     * If the {@code iomObject} is {@code null}, the {@code argObjects} is used to retrieve the {@link Viewable}.
+     */
     public static Viewable getContextClass(TransferDescription td, IomObject iomObject, Value argObjects) {
         if (iomObject != null) {
             return (Viewable) td.getElement(iomObject.getobjecttag());
@@ -44,6 +62,9 @@ public static Viewable getContextClass(TransferDescription td, IomObject iomObje
         return null;
     }
 
+    /**
+     * Get the collection of {@link IomObject} inside {@code argObjects} by following the provided {@code attributePath}.
+     */
     public static Collection<IomObject> evaluateAttributes(Validator validator, Value argObjects, PathEl[] attributePath) {
         Collection<IomObject> attributes = new ArrayList<>();
 
@@ -57,6 +78,9 @@ public static Collection<IomObject> evaluateAttributes(Validator validator, Valu
         return attributes;
     }
 
+    /**
+     * Applies the given function to each item in the collection and sums up the results.
+     */
     public static Double sum(Collection<IomObject> items, Function<IomObject, Double> func) {
         return items
                 .stream()

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/GetAreaIoxPlugin.java

@@ -7,10 +7,9 @@
 import ch.interlis.iox_j.jts.Iox2jtsext;
 import ch.interlis.iox_j.validator.Value;
 
-import java.util.ArrayList;
 import java.util.Collection;
 
-public class GetAreaIoxPlugin extends BaseInterlisFunction {
+public final class GetAreaIoxPlugin extends BaseInterlisFunction {
 
     @Override
     public String getQualifiedIliName() {

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/GetInGroupsIoxPlugin.java

@@ -5,15 +5,9 @@
 import ch.interlis.iom.IomObject;
 import ch.interlis.iox_j.validator.Value;
 
-import java.security.acl.Group;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
+import java.util.*;
 
-public class GetInGroupsIoxPlugin extends BaseInterlisFunction {
+public final class GetInGroupsIoxPlugin extends BaseInterlisFunction {
 
     private static Map<GroupKey, List<IomObject>> groups = new HashMap<>();
 
@@ -43,37 +37,40 @@ public Value evaluateInternal(String validationKind, String usageScope, IomObjec
         PathEl[] attributePath = EvaluationHelper.getAttributePathEl(validator, contextClass, argPath);
 
         GroupKey key = new GroupKey(inputObjects, validator.getValueFromObjectPath(null, contextObject, attributePath, null));
-        if(!groups.containsKey(key)){
-            FillGroups(inputObjects, attributePath);
+        if (!groups.containsKey(key)) {
+            fillGroups(inputObjects, attributePath);
         }
 
         return new Value(groups.get(key));
     }
 
-    private void FillGroups(Collection<IomObject> inputObjects, PathEl[] attributePath) {
+    private void fillGroups(Collection<IomObject> inputObjects, PathEl[] attributePath) {
         for (IomObject object: inputObjects) {
             GroupKey key = new GroupKey(inputObjects, validator.getValueFromObjectPath(null, object, attributePath, null));
-            if(!groups.containsKey(key)){
+            if (!groups.containsKey(key)) {
                 groups.put(key, new ArrayList<>());
             }
 
             groups.get(key).add(object);
         }
     }
 
-    private static class GroupKey
-    {
+    private static final class GroupKey {
         private Collection<IomObject> inputObjects;
         private Value groupId;
-        public GroupKey(Collection<IomObject> inputObjects, Value groupId){
+        GroupKey(Collection<IomObject> inputObjects, Value groupId) {
             this.inputObjects = inputObjects;
             this.groupId = groupId;
         }
 
         @Override
         public boolean equals(Object o) {
-            if (this == o) return true;
-            if (o == null || getClass() != o.getClass()) return false;
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
             GroupKey that = (GroupKey) o;
             return inputObjects.equals(that.inputObjects) && groupId.compareTo(that.groupId) == 0;
         }