cqfn#19 OCC

src/main/java/org/jpeek/metrics/cohesion/OCC.java

@@ -0,0 +1,276 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.jpeek.metrics.cohesion;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+import javassist.CannotCompileException;
+import javassist.CtClass;
+import javassist.CtField;
+import javassist.CtMethod;
+import org.jpeek.Base;
+import org.jpeek.Metric;
+import org.jpeek.metrics.Colors;
+import org.jpeek.metrics.JavassistClasses;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
+import org.xembly.Directive;
+
+/**
+ * Optimistic Class Cohesion (OCC).
+ *
+ * <p>There is no thread-safety guarantee.
+ *
+ * @author Vseslav Sekorin (vssekorin@gmail.com)
+ * @version $Id$
+ * @see <a href="https://www.researchgate.net/publication/268046583_A_Proposal_of_Class_Cohesion_Metrics_Using_Sizes_of_Cohesive_Parts">A Proposal of Class Cohesion Metrics Using Sizes of Cohesive Parts</a>
+ * @since 0.2
+ * @checkstyle AbbreviationAsWordInNameCheck (5 lines)
+ * @checkstyle ParameterNumberCheck (500 lines)
+ */
+public final class OCC implements Metric {
+
+ /**
+ * The base.
+ */
+ private final Base base;
+
+ /**
+ * Ctor.
+ * @param bse The base
+ */
+ public OCC(final Base bse) {
+ this.base = bse;
+ }
+
+ @Override
+ public Iterable<Directive> xembly() throws IOException {
+ return new JavassistClasses(
+ this.base,
+ OCC::cohesion,
+ // @checkstyle MagicNumberCheck (1 line)
+ new Colors(0.35d, 0.75d, true)
+ ).xembly();
+ }
+
+ /**
+ * Calculate OCC metric for a single Java class.
+ *
+ * @param ctc The .class file
+ * @return Metrics
+ */
+ private static double cohesion(final CtClass ctc) {
+ final List<String> ctmethods = Arrays.stream(ctc.getDeclaredMethods())
+ .map(CtMethod::getName)
+ .collect(Collectors.toList());
+ final int number = ctmethods.size();
+ final double result;
+ if (number == 1) {
+ result = 0;
+ } else {
+ result = maxRw(ctc, ctmethods) / (number - 1);
+ }
+ return result;
+ }
+
+ /**
+ * Maximum number of methods which are reachable.
+ *
+ * @param ctc The .class file
+ * @param ctmethods Methods
+ * @return The number
+ */
+ @SuppressWarnings({"PMD.UseVarargs", "PMD.CyclomaticComplexity",
+ "PMD.StdCyclomaticComplexity", "PMD.ModifiedCyclomaticComplexity",
+ "PMD.UseObjectForClearerAPI"})
+ private static double maxRw(
+ final CtClass ctc, final List<String> ctmethods) {
+ final ClassReader reader;
+ try {
+ reader = new ClassReader(ctc.toBytecode());
+ } catch (final IOException | CannotCompileException ex) {
+ throw new IllegalStateException(ex);
+ }
+ final Map<String, Set<String>> vars = new HashMap<>();
+ final Map<String, Set<String>> methods = new HashMap<>();
+ final List<String> ctfields = Arrays.stream(ctc.getDeclaredFields())
+ .map(CtField::getName)
+ .collect(Collectors.toList());
+ reader.accept(
+ //@checkstyle AnonInnerLengthCheck (50 lines)
+ new ClassVisitor(Opcodes.ASM6) {
+ @Override
+ public MethodVisitor visitMethod(
+ final int access, final String mtd, final String desc,
+ final String signature, final String[] exceptions) {
+ super.visitMethod(access, mtd, desc, signature, exceptions);
+ final Set<String> attrs = new HashSet<>();
+ final Set<String> names = new HashSet<>();
+ vars.put(mtd, attrs);
+ methods.put(mtd, names);
+ return new MethodVisitor(Opcodes.ASM6) {
+ @Override
+ public void visitFieldInsn(
+ final int opcode, final String owner,
+ final String attr, final String details) {
+ super.visitFieldInsn(opcode, owner, attr, details);
+ if (ctfields.contains(attr)) {
+ attrs.add(attr);
+ }
+ }
+ @Override
+ public void visitMethodInsn(
+ final int opcode, final String owner,
+ final String name, final String desc,
+ final boolean itf) {
+ super.visitMethodInsn(
+ opcode, owner, name, desc, itf
+ );
+ if (!name.equals(mtd) && ctmethods.contains(name)) {
+ names.add(name);
+ }
+ }
+ };
+ }
+ },
+ 0
+ );
+ methods.forEach(
+ (key, value) -> value.forEach(
+ item -> vars.get(key).addAll(vars.get(item))
+ )
+ );
+ final int number = ctmethods.size();
+ final boolean[][] reachability = new boolean[number][number];
+ boolean[][] result = new boolean[number][number];
+ boolean[][] current = new boolean[number][number];
+ for (int row = 0; row < number; ++row) {
+ for (int col = 0; col < number; ++col) {
+ reachability[row][col] = hasWeakConnection(
+ vars.get(ctmethods.get(row)),
+ vars.get(ctmethods.get(col))
+ );
+ current[row][col] = reachability[row][col];
+ result[row][col] = reachability[row][col];
+ }
+ }
+ for (int ind = 2; ind <= number; ++ind) {
+ current = multiply(current, reachability, number);
+ result = disjunction(current, result, number);
+ }
+ return maxWays(result, number);
+ }
+
+ /**
+ * Check weak-connection of two method.
+ *
+ * @param first First method's vars
+ * @param second Second method's vars
+ * @return Result
+ */
+ private static boolean hasWeakConnection(
+ final Set<?> first, final Set<?> second) {
+ boolean result = false;
+ for (final Object item : first) {
+ if (second.contains(item)) {
+ result = true;
+ break;
+ }
+ }
+ return result;
+ }
+
+ /**
+ * Multiply of two boolean matrix.
+ *
+ * @param first The first matrix
+ * @param second The second matrix
+ * @param size Matrix size
+ * @return Result matrix
+ */
+ private static boolean[][] multiply(
+ final boolean[][] first, final boolean[][] second, final int size) {
+ final boolean[][] result = new boolean[size][size];
+ //@checkstyle NestedForDepthCheck (10 lines)
+ for (int row = 0; row < size; ++row) {
+ for (int col = 0; col < size; ++col) {
+ for (int inner = 0; inner < size; ++inner) {
+ result[row][col] = result[row][col]
+ || first[row][inner] && second[inner][col];
+ }
+ }
+ }
+ return result;
+ }
+
+ /**
+ * Disjunction of two boolean matrix.
+ *
+ * @param first The first matrix
+ * @param second The second matrix
+ * @param size Matrix size
+ * @return Result matrix
+ */
+ private static boolean[][] disjunction(
+ final boolean[][] first, final boolean[][] second, final int size) {
+ final boolean[][] result = new boolean[size][size];
+ for (int row = 0; row < size; ++row) {
+ for (int col = 0; col < size; ++col) {
+ result[row][col] = first[row][col] || second[row][col];
+ }
+ }
+ return result;
+ }
+
+ /**
+ * The maximum number of paths in the reachability matrix.
+ *
+ * @param array Matrix
+ * @param size Size of matrix
+ * @return The number
+ */
+ private static int maxWays(final boolean[][] array, final int size) {
+ int result = 0;
+ for (int row = 0; row < size; ++row) {
+ int current = 0;
+ for (int col = 0; col < size; ++col) {
+ if (array[row][col] && row != col) {
+ ++current;
+ }
+ }
+ if (result < current) {
+ result = current;
+ }
+ }
+ return result;
+ }
+}

src/test/java/org/jpeek/metrics/cohesion/OCCTest.java

@@ -0,0 +1,98 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.jpeek.metrics.cohesion;
+
+import com.jcabi.matchers.XhtmlMatchers;
+import java.io.IOException;
+import java.nio.file.Paths;
+import org.hamcrest.MatcherAssert;
+import org.jpeek.DefaultBase;
+import org.jpeek.metrics.FakeBase;
+import org.junit.Test;
+import org.xembly.Xembler;
+
+/**
+ * Test case for {@link OCC}.
+ *
+ * @author Vseslav Sekorin (vssekorin@gmail.com)
+ * @version $Id$
+ * @since 0.2
+ * @checkstyle AbbreviationAsWordInNameCheck (5 lines)
+ * @checkstyle JavadocMethodCheck (500 lines)
+ */
+public final class OCCTest {
+
+ @Test
+ public void createsBigXmlReport() throws IOException {
+ MatcherAssert.assertThat(
+ XhtmlMatchers.xhtml(
+ new Xembler(
+ new OCC(
+ new DefaultBase(Paths.get("."))
+ ).xembly()
+ ).xmlQuietly()
+ ),
+ XhtmlMatchers.hasXPaths(
+ "/app/package/class[@id='OCCTest']",
+ "//class[@id='Base' and @value='0.0000']"
+ )
+ );
+ }
+
+ @Test
+ public void createsXmlReportForYellowClass() throws IOException {
+ MatcherAssert.assertThat(
+ XhtmlMatchers.xhtml(
+ new Xembler(
+ new OCC(
+ new FakeBase("Test")
+ ).xembly()
+ ).xmlQuietly()
+ ),
+ XhtmlMatchers.hasXPaths(
+ "/app/package/class[@id='Test']",
+ "//class[@id='Test' and @value='0.5000']",
+ "//class[@id='Test' and @color='yellow']"
+ )
+ );
+ }
+
+ @Test
+ public void createsXmlReportForRedClass() throws IOException {
+ MatcherAssert.assertThat(
+ XhtmlMatchers.xhtml(
+ new Xembler(
+ new OCC(
+ new FakeBase("C")
+ ).xembly()
+ ).xmlQuietly()
+ ),
+ XhtmlMatchers.hasXPaths(
+ "/app/package/class[@id='C']",
+ "//class[@id='C' and @value='1.0000']",
+ "//class[@id='C' and @color='red']"
+ )
+ );
+ }
+}

src/test/resources/org/jpeek/C.java

@@ -0,0 +1,19 @@
+public class C {
+ private int a1, a2;
+
+ public void m1(int x) {
+ this.a1 = x;
+ }
+
+ public void m2(int y) {
+ this.a2 = y;
+ }
+
+ public int m3() {
+ return this.a1 + this.a2;
+ }
+
+ public void m4() {
+ this.m1(0);
+ }
+}