src/main/java/org/apache/maven/plugins/pmd/exec/PmdResult.java

/*
 * 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
 *
 *   http://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.maven.plugins.pmd.exec;

import java.io.File;
import java.io.FileInputStream;
import java.io.FilterReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.apache.maven.plugins.pmd.model.PmdErrorDetail;
import org.apache.maven.plugins.pmd.model.PmdFile;
import org.apache.maven.plugins.pmd.model.ProcessingError;
import org.apache.maven.plugins.pmd.model.SuppressedViolation;
import org.apache.maven.plugins.pmd.model.Violation;
import org.apache.maven.plugins.pmd.model.io.xpp3.PmdXpp3Reader;
import org.apache.maven.reporting.MavenReportException;

/**
 * Provides access to the result of the pmd analysis.
 */
public class PmdResult {
    private final List<ProcessingError> processingErrors = new ArrayList<>();
    private final List<Violation> violations = new ArrayList<>();
    private final List<SuppressedViolation> suppressedViolations = new ArrayList<>();

    public static final PmdResult EMPTY = new PmdResult();

    private PmdResult() {}

    public PmdResult(File pmdFile, String encoding) throws MavenReportException {
        loadResult(pmdFile, encoding);
    }

    public boolean hasViolations() {
        return !violations.isEmpty();
    }

    private void loadResult(File pmdFile, String encoding) throws MavenReportException {
        try (Reader reader1 = new BomFilter(encoding, new InputStreamReader(new FileInputStream(pmdFile), encoding))) {
            PmdXpp3Reader reader = new PmdXpp3Reader();
            PmdErrorDetail details = reader.read(reader1, false);
            processingErrors.addAll(details.getErrors());
            suppressedViolations.addAll(details.getSuppressedViolations());

            for (PmdFile file : details.getFiles()) {
                String filename = file.getName();
                for (Violation violation : file.getViolations()) {
                    violation.setFileName(filename);
                    violations.add(violation);
                }
            }
        } catch (Exception e) {
            throw new MavenReportException(e.getMessage(), e);
        }
    }

    // Note: This seems to be a bug in PMD's XMLRenderer. The BOM is rendered multiple times.
    // once at the beginning of the file, which is Ok, but also in the middle of the file.
    // This filter just skips all BOMs if the encoding is not UTF-8
    private static class BomFilter extends FilterReader {
        private static final char BOM = '\uFEFF';
        private final boolean filter;

        BomFilter(String encoding, Reader in) {
            super(in);
            filter = !"UTF-8".equalsIgnoreCase(encoding);
        }

        @Override
        public int read() throws IOException {
            int c = super.read();

            if (!filter) {
                return c;
            }

            while (c != -1 && c == BOM) {
                c = super.read();
            }
            return c;
        }

        @Override
        public int read(char[] cbuf, int off, int len) throws IOException {
            int count = super.read(cbuf, off, len);

            if (!filter) {
                return count;
            }

            if (count != -1) {
                for (int i = off; i < off + count; i++) {
                    if (cbuf[i] == BOM) {
                        // shift the content one char to the left
                        System.arraycopy(cbuf, i + 1, cbuf, i, off + count - 1 - i);
                        count--;
                    }
                }
            }
            return count;
        }
    }

    public Collection<Violation> getViolations() {
        return violations;
    }

    public Collection<SuppressedViolation> getSuppressedViolations() {
        return suppressedViolations;
    }

    public Collection<ProcessingError> getErrors() {
        return processingErrors;
    }
}