#33 "source code style rule definition"

- usage of static and wildcard imports

README.md

@@ -243,3 +243,5 @@ Unresolvable methods (no coverage information available):
         1. don't overuse inner types, as soon as the type is also useful in some other context it should be a top-level type
 1. don't use checked (and unchecked) exceptions for program flow, always prefer returning proper result types (exceptions are reserved for real, unexpected errors)
     1. wrapping an `IOException` with `UncheckedIOException` (or more general any exception in a `IllegalStateException`) is okay but takes away the possibility from the caller to react to errors (for example by skipping a single file that cause an `IOException` while reading it)
+1. no static imports in production code (only allowed in tests)
+1. no wildcard imports in general

test-gap-analysis/src/main/java/com/scheible/testgapanalysis/analysis/testgap/TestGapAnalysis.java

@@ -1,9 +1,8 @@
 package com.scheible.testgapanalysis.analysis.testgap;
 
-import static java.util.Collections.emptySet;
-
 import java.io.File;
 import java.util.AbstractMap;
+import java.util.Collections;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Optional;
@@ -59,7 +58,7 @@ public TestGapReport run(final File workDir, final Set<File> jaCoCoReportFiles,
 	}
 
 	private RepositoryResult identifyFileChanges(final Optional<String> referenceCommitHash, final File workDir) {
-		Set<NewOrChangedFile> newOrChangedFiles = emptySet();
+		Set<NewOrChangedFile> newOrChangedFiles = Collections.emptySet();
 
 		final RepositoryStatus status = referenceCommitHash
 				.map(h -> gitDiffer.ofCommitComparedToHead(workDir, h, NON_TEST_JAVA_FILE))

test-gap-analysis/src/main/java/com/scheible/testgapanalysis/common/FilesUtils.java

@@ -1,7 +1,5 @@
 package com.scheible.testgapanalysis.common;
 
-import static java.util.Objects.requireNonNull;
-
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
@@ -10,6 +8,7 @@
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Objects;
 import java.util.Set;
 import java.util.stream.Collectors;
 
@@ -31,7 +30,7 @@ public static String readUtf8(final Class<?> anchor, final String name) {
 	}
 
 	public static String readUtf8(final InputStream inputStream) {
-		try (InputStream tryCatchInputStream = requireNonNull(inputStream)) {
+		try (InputStream tryCatchInputStream = Objects.requireNonNull(inputStream)) {
 
 			final ByteArrayOutputStream result = new ByteArrayOutputStream();
 			final byte[] buffer = new byte[1024];
@@ -48,7 +47,7 @@ public static String readUtf8(final InputStream inputStream) {
 
 	public static String readUtf8(final File file) {
 		try {
-			return new String(Files.readAllBytes(requireNonNull(file).toPath()), UTF_8_CHARSET);
+			return new String(Files.readAllBytes(Objects.requireNonNull(file).toPath()), UTF_8_CHARSET);
 		} catch (IOException ex) {
 			throw new UncheckedIOException(ex);
 		}

test-gap-analysis/src/main/java/com/scheible/testgapanalysis/jacoco/JaCoCoReportParser.java

@@ -1,7 +1,5 @@
 package com.scheible.testgapanalysis.jacoco;
 
-import static javax.xml.XMLConstants.FEATURE_SECURE_PROCESSING;
-
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
@@ -18,6 +16,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import javax.xml.XMLConstants;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
@@ -53,7 +52,7 @@ public Set<MethodWithCoverageInfo> getMethodCoverage(final File reportXmlFile) {
 	private Set<MethodWithCoverageInfo> getMethodCoverage(final InputSource inputSource) {
 		try {
 			final DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
-			builderFactory.setFeature(FEATURE_SECURE_PROCESSING, true);
+			builderFactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
 			final DocumentBuilder builder = builderFactory.newDocumentBuilder();
 			builder.setEntityResolver((String publicId,
 					String systemId) -> systemId.contains("report.dtd") ? new InputSource(new StringReader("")) : null);

test-gap-analysis/src/main/java/com/scheible/testgapanalysis/jacoco/resolver/CoverageResolver.java

@@ -1,12 +1,7 @@
 package com.scheible.testgapanalysis.jacoco.resolver;
 
-import static java.util.Collections.emptyMap;
-import static java.util.Collections.emptySet;
-
-import static com.scheible.testgapanalysis.common.JavaMethodUtils.normalizeMethodArguments;
-import static com.scheible.testgapanalysis.common.JavaMethodUtils.parseDescriptorArguments;
-
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -19,6 +14,7 @@
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
+import com.scheible.testgapanalysis.common.JavaMethodUtils;
 import com.scheible.testgapanalysis.jacoco.MethodWithCoverageInfo;
 import com.scheible.testgapanalysis.parser.ParsedMethod;
 
@@ -60,7 +56,7 @@ public CoverageResult resolve(final Set<ParsedMethod> methods) {
 	CoverageResult resolveType(final TopLevelType type, final Set<ParsedMethod> methods) {
 		final CoverageResult result = new CoverageResult();
 
-		final Set<MethodWithCoverageInfo> coverage = coverageReport.getOrDefault(type, emptySet());
+		final Set<MethodWithCoverageInfo> coverage = coverageReport.getOrDefault(type, Collections.emptySet());
 
 		result.add(resolveInitializers(filter(methods, ParsedMethod::isInitializer), coverage));
 		result.add(resolveStaticInitializers(filter(methods, ParsedMethod::isStaticInitializer), coverage));
@@ -84,7 +80,7 @@ private CoverageResult resolveInitializers(final Set<ParsedMethod> initializers,
 		if (initializers.size() == 1 && coverageConstructors.size() == 1) {
 			final Map<ParsedMethod, MethodWithCoverageInfo> resolvedInitializers = new HashMap<>();
 			resolvedInitializers.put(initializers.iterator().next(), coverageConstructors.get(0));
-			return new CoverageResult(resolvedInitializers, emptySet());
+			return new CoverageResult(resolvedInitializers, Collections.emptySet());
 		} else {
 			// try to find a constructor with covered code, if there is none use any non-covered constructor
 			final Optional<MethodWithCoverageInfo> firstConstructorCoverage = coverageConstructors.stream()
@@ -94,7 +90,7 @@ private CoverageResult resolveInitializers(final Set<ParsedMethod> initializers,
 			if (firstConstructorCoverage.isPresent()) {
 				final Map<ParsedMethod, MethodWithCoverageInfo> resolvedInitializers = new HashMap<>();
 				initializers.forEach(im -> resolvedInitializers.put(im, firstConstructorCoverage.get()));
-				return new CoverageResult(resolvedInitializers, emptySet());
+				return new CoverageResult(resolvedInitializers, Collections.emptySet());
 			}
 		}
 
@@ -113,7 +109,7 @@ private CoverageResult resolveStaticInitializers(final Set<ParsedMethod> staticI
 		if (!coverageStaticInitializers.isEmpty()) { // make sure that a coverage report is there
 			final Map<ParsedMethod, MethodWithCoverageInfo> resolvedStaticInitializers = new HashMap<>();
 			staticInitializers.forEach(im -> resolvedStaticInitializers.put(im, coverageStaticInitializers.get(0)));
-			return new CoverageResult(resolvedStaticInitializers, emptySet());
+			return new CoverageResult(resolvedStaticInitializers, Collections.emptySet());
 		}
 
 		return new CoverageResult();
@@ -132,8 +128,8 @@ private CoverageResult resolveConstructor(final Set<ParsedMethod> constructors,
 		final Set<ParsedMethod> unresolved = new HashSet<>();
 
 		for (final ParsedMethod constructor : constructors) {
-			final List<String> normalizedConstructorArguments = new ArrayList<>(
-					normalizeMethodArguments(constructor.getArgumentTypes(), constructor.getTypeParameters()));
+			final List<String> normalizedConstructorArguments = new ArrayList<>(JavaMethodUtils
+					.normalizeMethodArguments(constructor.getArgumentTypes(), constructor.getTypeParameters()));
 
 			// The constructors of enums have two additional parameter of type String and int. Most likely the name and
 			// index of the enum const is passed via this parameter.
@@ -150,8 +146,8 @@ private CoverageResult resolveConstructor(final Set<ParsedMethod> constructors,
 			final List<MethodWithCoverageInfo> coverageConstructors = coverage.stream()
 					.filter(MethodWithCoverageInfo::isConstructor)
 					.filter(mwci -> mwci.getEnclosingSimpleName().equals(constructor.getEnclosingSimpleName()))
-					.filter(mwci -> normalizedConstructorArguments.equals(
-							normalizeMethodArguments(parseDescriptorArguments(mwci.getDescription()), emptyMap())))
+					.filter(mwci -> normalizedConstructorArguments.equals(JavaMethodUtils.normalizeMethodArguments(
+							JavaMethodUtils.parseDescriptorArguments(mwci.getDescription()), Collections.emptyMap())))
 					.collect(Collectors.toList());
 			if (coverageConstructors.size() == 1) {
 				resolved.put(constructor, coverageConstructors.get(0));
@@ -177,8 +173,8 @@ private CoverageResult resolveNonLambdaMethods(final Set<ParsedMethod> methods,
 			for (final MethodWithCoverageInfo coverageMethod : coverage.stream()
 					.filter(MethodWithCoverageInfo::isNonLambdaMethod).collect(Collectors.toSet())) {
 				if (method.containsLine(coverageMethod.getLine()) && method.getName().equals(coverageMethod.getName())
-						&& method.getArgumentCount() == parseDescriptorArguments(coverageMethod.getDescription())
-								.size()) {
+						&& method.getArgumentCount() == JavaMethodUtils
+								.parseDescriptorArguments(coverageMethod.getDescription()).size()) {
 					candidates.add(coverageMethod);
 				}
 			}
@@ -249,9 +245,8 @@ private CoverageResult resolveLambdaMethodsCluster(final Entry<ParsedMethod, Set
 			boolean withoutErrors = true;
 
 			for (int i = 0; i < lambdaCoverage.size(); i++) {
-				if (lambdas.get(i)
-						.getArgumentCount() <= parseDescriptorArguments(lambdaCoverage.get(i).getDescription())
-								.size()) {
+				if (lambdas.get(i).getArgumentCount() <= JavaMethodUtils
+						.parseDescriptorArguments(lambdaCoverage.get(i).getDescription()).size()) {
 					currentResolved.put(lambdas.get(i), lambdaCoverage.get(i));
 				} else {
 					withoutErrors = false;
@@ -260,11 +255,11 @@ private CoverageResult resolveLambdaMethodsCluster(final Entry<ParsedMethod, Set
 			}
 
 			if (withoutErrors) {
-				return new CoverageResult(currentResolved, emptySet());
+				return new CoverageResult(currentResolved, Collections.emptySet());
 			}
 		}
 
-		return new CoverageResult(emptyMap(), new HashSet<>(lambdas));
+		return new CoverageResult(Collections.emptyMap(), new HashSet<>(lambdas));
 	}
 
 	private static Map<TopLevelType, Set<ParsedMethod>> groupMethodsByType(final Set<ParsedMethod> methods) {

test-gap-analysis/src/main/java/com/scheible/testgapanalysis/parser/ParsedMethod.java

@@ -1,7 +1,5 @@
 package com.scheible.testgapanalysis.parser;
 
-import static java.util.Collections.emptyMap;
-
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -59,8 +57,8 @@ public enum MethodType {
 				: IntStream.range(0, builder.argumentCount).boxed().map(i -> "Object").collect(Collectors.toList()));
 
 		argumentCount = argumentTypes.size();
-		this.typeParameters = Collections
-				.unmodifiableMap(builder.typeParameters != null ? new HashMap<>(builder.typeParameters) : emptyMap());
+		this.typeParameters = Collections.unmodifiableMap(
+				builder.typeParameters != null ? new HashMap<>(builder.typeParameters) : Collections.emptyMap());
 		this.outerDeclaringType = builder.outerDeclaringType;
 	}
 

test-gap-analysis/src/test/java/com/scheible/testgapanalysis/analysis/testgap/AnalysisTestGapSubModule.java

@@ -2,7 +2,6 @@
 
 import com.scheible.pocketsaw.api.SubModule;
 import com.scheible.testgapanalysis.ExternalFunctionalities.Slf4j;
-import com.scheible.testgapanalysis.analysis.*;
 import com.scheible.testgapanalysis.common.CommonSubModule;
 import com.scheible.testgapanalysis.git.GitSubModule;
 import com.scheible.testgapanalysis.jacoco.JaCoCoSubModule;