/*
* 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.tools.ant.util;
import java.util.StringTokenizer;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
/**
* Utility class to contain version numbers in "Dewey Decimal"
* syntax. Numbers in the "Dewey Decimal" syntax consist of positive
* decimal integers separated by periods ".". For example, "2.0" or
* "1.2.3.4.5.6.7". This allows an extensible number to be used to
* represent major, minor, micro, etc versions. The version number
* must begin with a number.
*
*/
public class DeweyDecimal implements Comparable<DeweyDecimal> {
/** Array of components that make up DeweyDecimal */
private final int[] components;
/**
* Construct a DeweyDecimal from an array of integer components.
*
* @param components an array of integer components.
*/
public DeweyDecimal(final int[] components) {
this.components = new int[components.length];
System.arraycopy(components, 0, this.components, 0, components.length);
}
/**
* Construct a DeweyDecimal from string in DeweyDecimal format.
*
* @param string the string in dewey decimal format
* @exception NumberFormatException if string is malformed
*/
public DeweyDecimal(final String string)
throws NumberFormatException {
final StringTokenizer tokenizer = new StringTokenizer(string, ".", true);
final int size = tokenizer.countTokens();
components = new int[ (size + 1) / 2 ];
for (int i = 0; i < components.length; i++) {
final String component = tokenizer.nextToken();
if (component.length() == 0) {
throw new NumberFormatException("Empty component in string");
}
components[ i ] = Integer.parseInt(component);
//Strip '.' token
if (tokenizer.hasMoreTokens()) {
tokenizer.nextToken();
//If it ended in a dot, throw an exception
if (!tokenizer.hasMoreTokens()) {
throw new NumberFormatException("DeweyDecimal ended in a '.'");
}
}
}
}
/**
* Return number of components in <code>DeweyDecimal</code>.
*
* @return the number of components in dewey decimal
*/
public int getSize() {
return components.length;
}
/**
* Return the component at specified index.
*
* @param index the index of components
* @return the value of component at index
*/
public int get(final int index) {
return components[ index ];
}
/**
* Return <code>true</code> if this <code>DeweyDecimal</code> is
* equal to the other <code>DeweyDecimal</code>.
*
* @param other the other DeweyDecimal
* @return true if equal to other DeweyDecimal, false otherwise
*/
public boolean isEqual(final DeweyDecimal other) {
final int max = Math.max(other.components.length, components.length);
for (int i = 0; i < max; i++) {
final int component1 = (i < components.length) ? components[ i ] : 0;
final int component2 = (i < other.components.length) ? other.components[ i ] : 0;
if (component2 != component1) {
return false;
}
}
return true; // Exact match
}
/**
* Return <code>true</code> if this <code>DeweyDecimal</code> is
* less than the other <code>DeweyDecimal</code>.
*
* @param other the other DeweyDecimal
* @return true if less than other DeweyDecimal, false otherwise
*/
public boolean isLessThan(final DeweyDecimal other) {
return !isGreaterThanOrEqual(other);
}
/**
* Return <code>true</code> if this <code>DeweyDecimal</code> is
* less than or equal to the other <code>DeweyDecimal</code>.
*
* @param other the other DeweyDecimal
* @return true if less than or equal to other DeweyDecimal, false otherwise
*/
public boolean isLessThanOrEqual(final DeweyDecimal other) {
return !isGreaterThan(other);
}
/**
* Return <code>true</code> if this <code>DeweyDecimal</code> is
* greater than the other <code>DeweyDecimal</code>.
*
* @param other the other DeweyDecimal
* @return true if greater than other DeweyDecimal, false otherwise
*/
public boolean isGreaterThan(final DeweyDecimal other) {
final int max = Math.max(other.components.length, components.length);
for (int i = 0; i < max; i++) {
final int component1 = (i < components.length) ? components[ i ] : 0;
final int component2 = (i < other.components.length) ? other.components[ i ] : 0;
if (component2 > component1) {
return false;
}
if (component2 < component1) {
return true;
}
}
return false; // Exact match
}
/**
* Return <code>true</code> if this <code>DeweyDecimal</code> is
* greater than or equal to the other <code>DeweyDecimal</code>.
*
* @param other the other DeweyDecimal
* @return true if greater than or equal to other DeweyDecimal, false otherwise
*/
public boolean isGreaterThanOrEqual(final DeweyDecimal other) {
final int max = Math.max(other.components.length, components.length);
for (int i = 0; i < max; i++) {
final int component1 = (i < components.length) ? components[ i ] : 0;
final int component2 = (i < other.components.length) ? other.components[ i ] : 0;
if (component2 > component1) {
return false;
}
if (component2 < component1) {
return true;
}
}
return true; // Exact match
}
/**
* Return string representation of <code>DeweyDecimal</code>.
*
* @return the string representation of DeweyDecimal.
*/
@Override public String toString() {
return IntStream.of(components).mapToObj(Integer::toString)
.collect(Collectors.joining("."));
}
/**
* Compares this DeweyDecimal with another one.
*
* @param other another DeweyDecimal to compare with
* @return result
* @see java.lang.Comparable#compareTo(Object)
*/
@Override
public int compareTo(DeweyDecimal other) {
final int max = Math.max(other.components.length, components.length);
for (int i = 0; i < max; i++) {
final int component1 = (i < components.length) ? components[ i ] : 0;
final int component2 = (i < other.components.length) ? other.components[ i ] : 0;
if (component1 != component2) {
return component1 - component2;
}
}
return 0;
}
@Override public int hashCode() {
return toString().hashCode();
}
@Override public boolean equals(Object o) {
return o instanceof DeweyDecimal && isEqual((DeweyDecimal) o);
}
}