IdentifyingNameValidator.java

/*
 * Copyright (C) 2012 Google Inc.
 *
 * Licensed 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 interactivespaces.domain.support;

import interactivespaces.domain.support.DomainValidationResult.DomainValidationResultType;

import java.util.regex.Pattern;

/**
 * A validator for identifying names.
 *
 * @author Keith M. Hughes
 */
public class IdentifyingNameValidator implements Validator {

  /**
   * Pattern for the identifying name.
   */
  public static final Pattern PATTERN = Pattern
      .compile("[a-zA-Z][a-zA-Z0-9_]*(\\.[a-zA-Z][a-zA-Z0-9_]*)*");

  @Override
  public DomainValidationResult validate(String candidate) {
    candidate = candidate.trim();

    if (candidate.isEmpty()) {
      return new DomainValidationResult(DomainValidationResultType.ERRORS,
          "An identifying name is required.");
    }

    if (!PATTERN.matcher(candidate).matches()) {
      return new DomainValidationResult(DomainValidationResultType.ERRORS,
          "An identifying name must be of the form a.b.c.c\n"
              + "where each section starts with a letter and\n"
              + "continues with letters, digits, or underscores.");
    }

    return new DomainValidationResult(DomainValidationResultType.OK, null);
  }
}