AttributesNode.java

/*
 * Copyright (C) 2010, Red Hat Inc. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */
package org.eclipse.jgit.attributes;

import static java.nio.charset.StandardCharsets.UTF_8;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Represents a bundle of attributes inherited from a base directory.
 *
 * This class is not thread safe, it maintains state about the last match.
 *
 * @since 3.7
 */
public class AttributesNode {
    /** The rules that have been parsed into this node. */
    private final List<AttributesRule> rules;

    /**
     * Create an empty ignore node with no rules.
     */
    public AttributesNode() {
        rules = new ArrayList<>();
    }

    /**
     * Create an ignore node with given rules.
     *
     * @param rules
     *            list of rules.
     */
    public AttributesNode(List<AttributesRule> rules) {
        this.rules = rules;
    }

    /**
     * Parse files according to gitattribute standards.
     *
     * @param in
     *            input stream holding the standard ignore format. The caller is
     *            responsible for closing the stream.
     * @throws java.io.IOException
     *             Error thrown when reading an ignore file.
     */
    public void parse(InputStream in) throws IOException {
        BufferedReader br = asReader(in);
        String txt;
        while ((txt = br.readLine()) != null) {
            txt = txt.trim();
            if (txt.length() > 0 && !txt.startsWith("#") /* Comments *///$NON-NLS-1$
                    && !txt.startsWith("!") /* Negative pattern forbidden for attributes */) { //$NON-NLS-1$
                int patternEndSpace = txt.indexOf(' ');
                int patternEndTab = txt.indexOf('\t');

                final int patternEnd;
                if (patternEndSpace == -1)
                    patternEnd = patternEndTab;
                else if (patternEndTab == -1)
                    patternEnd = patternEndSpace;
                else
                    patternEnd = Math.min(patternEndSpace, patternEndTab);

                if (patternEnd > -1)
                    rules.add(new AttributesRule(txt.substring(0, patternEnd),
                            txt.substring(patternEnd + 1).trim()));
            }
        }
    }

    private static BufferedReader asReader(InputStream in) {
        return new BufferedReader(new InputStreamReader(in, UTF_8));
    }

    /**
     * Getter for the field <code>rules</code>.
     *
     * @return list of all ignore rules held by this node
     */
    public List<AttributesRule> getRules() {
        return Collections.unmodifiableList(rules);
    }

}