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Common library used by some SonarLint flavors

There is a newer version: 10.2.0.78029

/*
 * SonarQube, open source software quality management tool.
 * Copyright (C) 2008-2013 SonarSource
 * mailto:contact AT sonarsource DOT com
 *
 * SonarQube is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * SonarQube is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.channel;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * The RegexChannel can be used to be called each time the next characters in the character stream match a regular expression
 */
public abstract class RegexChannel extends Channel {

  private final StringBuilder tmpBuilder = new StringBuilder();
  private final Matcher matcher;

  /**
   * Create a RegexChannel object with the required regular expression
   *
   * @param regex
   *          regular expression to be used to try matching the next characters in the stream
   */
  public RegexChannel(String regex) {
    matcher = Pattern.compile(regex).matcher("");
  }

  @Override
  public final boolean consume(CodeReader code, O output) {
    if (code.popTo(matcher, tmpBuilder) > 0) {
      consume(tmpBuilder, output);
      tmpBuilder.delete(0, tmpBuilder.length());
      return true;
    }
    return false;
  }

  /**
   * The consume method is called each time the regular expression used to create the RegexChannel object matches the next characters in the
   * character streams.
   *
   * @param token
   *          the token consumed in the character stream and matching the regular expression
   * @param the
   *          OUPUT object which can be optionally fed
   */
  protected abstract void consume(CharSequence token, O output);

}