content: /*
   * Created on Oct 23, 2010
   *
   * 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.
   *
   * Copyright @2010-2012 the original author or authors.
   */
  package org.fest.assertions.data;
  
  import static org.fest.util.Objects.*;
  import static org.fest.util.Preconditions.checkNotNull;
  
  /**
   * A positive offset.
   *
   * @param <T> the type of the offset value.
   *
   * @author Alex Ruiz
   * @author Yvonne Wang
   */
  public class Offset<T extends Number> {
    public final T value;
  
    /**
     * Creates a new {@link Offset}.
     *
     * @param value the value of the offset.
     * @return the created {@code Offset}.
     * @throws NullPointerException if the given value is {@code null}.
     * @throws IllegalArgumentException if the given value is negative.
     */
    public static Offset<Double> offset(Double value) {
      checkNotNull(value);
      if (value.doubleValue() < 0d) {
        throw valueNotPositive();
      }
      return new Offset<Double>(value);
    }
  
    /**
     * Creates a new {@link Offset}.
     *
     * @param value the value of the offset.
     * @return the created {@code Offset}.
     * @throws NullPointerException if the given value is {@code null}.
     * @throws IllegalArgumentException if the given value is negative.
     */
    public static Offset<Float> offset(Float value) {
      checkNotNull(value);
      if (value.floatValue() < 0f) {
        throw valueNotPositive();
      }
      return new Offset<Float>(value);
    }
  
    /**
     * Creates a new {@link Offset}.
     *
     * @param value the value of the offset.
     * @return the created {@code Offset}.
     * @throws NullPointerException if the given value is {@code null}.
     * @throws IllegalArgumentException if the given value is negative.
     */
    public static Offset<Integer> offset(Integer value) {
      checkNotNull(value);
      if (value.intValue() < 0) {
        throw valueNotPositive();
      }
      return new Offset<Integer>(value);
    }
  
    private static IllegalArgumentException valueNotPositive() {
      return new IllegalArgumentException("The value of the offset should be greater than zero");
    }
  
    private Offset(T value) {
      this.value = value;
    }
  
    @Override
    public boolean equals(Object obj) {
      if (this == obj) {
        return true;
      }
      if (obj == null) {
        return false;
      }
      if (getClass() != obj.getClass()) {
        return false;
      }
      Offset<?> other = (Offset<?>) obj;
      return areEqual(value, other.value);
    }
  
    @Override
    public int hashCode() {
      int result = 1;
      result = HASH_CODE_PRIME * result + hashCodeFor(value);
      return result;
    }
  
    @Override
    public String toString() {
      return String.format("%s[value=%s]", getClass().getSimpleName(), value);
    }
  }
  