CPDRunner

libvcs4j-tools/src/main/java/de/unibremen/informatik/st/libvcs4j/pmd/CPDDetectionResult.java

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+package de.unibremen.informatik.st.libvcs4j.pmd;
+
+import de.unibremen.informatik.st.libvcs4j.VCSFile;
+import lombok.NonNull;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+/**
+ * The detection result of {@link CPDRunner}.
+ */
+public class CPDDetectionResult {
+
+    /**
+     * The detected violations.
+     */
+    private final List<CPDDuplication> violations;
+
+    /**
+     * Creates a new instance with given violations.
+     *
+     * @param violations
+     * 		The violations to store (flat copied, {@code null} values are
+     * 		filtered out).
+     * @throws NullPointerException
+     * 		If {@code violations} is {@code null}.
+     */
+    public CPDDetectionResult(@NonNull List<CPDDuplication> violations) {
+        this.violations = violations.stream()
+                .filter(Objects::nonNull)
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * Returns the violations.
+     *
+     * @return
+     * 		A copy of the internal list.
+     */
+    public List<CPDDuplication> getViolations() {
+        return new ArrayList<>(violations);
+    }
+
+
+    /**
+     * Returns all violations detected in {@code file}. Returns an empty list
+     * if {@code file} is {@code null} or was not analyzed.
+     *
+     * @param file
+     * 		The requested file.
+     * @return
+     * 		All violations detected in {@code file}.
+     */
+    public List<CPDDuplication> violationsOf(final VCSFile file) {
+        if(file == null){return new ArrayList<>();}
+        List<CPDDuplication> violationsOfFile = new ArrayList<CPDDuplication>();
+        for(CPDDuplication v : violations){
+            List<VCSFile.Range> ranges = v.getRanges();
+            for(VCSFile.Range range : ranges){
+                if(range.getFile().getRelativePath() == file.getRelativePath()){
+                    violationsOfFile.add(v);
+                    break;
+                }
+            }
+        }
+        return violationsOfFile;
+    }
+}

libvcs4j-tools/src/main/java/de/unibremen/informatik/st/libvcs4j/pmd/CPDDuplication.java

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+package de.unibremen.informatik.st.libvcs4j.pmd;
+
+import de.unibremen.informatik.st.libvcs4j.VCSFile;
+import de.unibremen.informatik.st.libvcs4j.mapping.Mappable;
+import lombok.NonNull;
+import lombok.Value;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * A readonly representation of a violation detected by CPD.
+ */
+@Value
+public final class CPDDuplication implements Mappable<String> {
+
+    /**
+     * The ranges of this violation.
+     */
+    @NonNull
+    private final List<VCSFile.Range> ranges;
+
+    /**
+     * Amount of lines that are duplicated
+     */
+    @NonNull
+    private final int lines;
+
+    /**
+     * Amount of tokens that the duplication shares
+     */
+    @NonNull
+    private final int tokens;
+
+    @Override
+    public List<VCSFile.Range> getRanges() {
+        return new ArrayList<>(ranges);
+    }
+
+    @Override
+    public Optional<String> getMetadata() {
+        return Optional.of("cpd-clone");
+    }
+}

libvcs4j-tools/src/main/java/de/unibremen/informatik/st/libvcs4j/pmd/CPDRunner.java

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+package de.unibremen.informatik.st.libvcs4j.pmd;
+
+import de.unibremen.informatik.st.libvcs4j.Revision;
+import lombok.Getter;
+import lombok.NonNull;
+import lombok.Setter;
+import lombok.extern.slf4j.Slf4j;
+import net.sourceforge.pmd.cpd.CPD;
+import org.xml.sax.SAXException;
+
+import javax.xml.parsers.ParserConfigurationException;
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Allows to configure and run CPD on {@link Revision} instances.
+ */
+@Slf4j
+public class CPDRunner {
+
+    /**
+     * Minimum Tokens that have to match for duplicate to be reported
+     */
+    @Getter
+    private int minimumTokens;
+
+    /**
+     * Creates a new CPD runner.
+     */
+    public CPDRunner(final int pMinimumTokens){
+        minimumTokens = pMinimumTokens;
+    }
+
+    /**
+     * Analyzes the given revision.
+     *
+     * @param revision
+     * 		The revision to analyze.
+     * @return
+     * 		The detection result.
+     * @throws NullPointerException
+     * 		If {@code revision} is {@code null}.
+     * @throws IOException
+     * 		If an error occurred while analyzing {@code revision}.
+     */
+    public CPDDetectionResult analyze(@NonNull final Revision revision)
+            throws IOException {
+
+        final List<String> args = new ArrayList<>();
+        // language
+        args.add("--language");
+        args.add("java");
+        // tokens
+        args.add("--minimum-tokens");
+        args.add(String.valueOf(minimumTokens));
+        // input
+        args.add("--files");
+        args.add(revision.getOutput().toString());
+        // format
+        args.add("--format");
+        args.add("xml");
+        // encoding
+        args.add("--encoding");
+        args.add("utf-8");
+        // Skip files that can't be tokenized instead of throwing Exceptions
+        args.add("--skip-lexical-errors");
+        // Ignore Identifiers, Literals and Annotations to detect Type 2 Clones
+        args.add("--ignore-identifiers");
+        args.add("--ignore-literals");
+        args.add("--ignore-annotations");
+
+
+        // Temporarily redirect stdout to a string.
+        final PrintStream stdout = System.out;
+        final ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        final PrintStream ps = new PrintStream(bos);
+        System.setOut(ps);
+        try {
+            System.setProperty("net.sourceforge.pmd.cli.noExit","true");
+            CPD.main(args.toArray(String[]::new));
+            // According to PMD the resulting xml is UTF-8 encoded.
+            final String output = bos.toString(StandardCharsets.UTF_8.name());
+
+            // Parse output
+            final SAXParserFactory factory = SAXParserFactory.newInstance();
+            final SAXParser saxParser = factory.newSAXParser();
+            final InputStream bis = new ByteArrayInputStream(
+                    output.getBytes(StandardCharsets.UTF_8.name()));
+            CPDSaxHandler handler = new CPDSaxHandler(revision.getFiles());
+            saxParser.parse(bis, handler);
+
+            // Result
+            return new CPDDetectionResult(handler.getViolations());
+        } catch (final UnsupportedOperationException | SAXException
+                | ParserConfigurationException e) {
+            throw new IOException(e);
+        } finally {
+            // Make sure to reset stdout.
+            System.setOut(stdout);
+        }
+    }
+}