com.day.cq.commons.Version Maven / Gradle / Ivy
/*
* Copyright 1997-2009 Day Management AG
* Barfuesserplatz 6, 4001 Basel, Switzerland
* All Rights Reserved.
*
* This software is the confidential and proprietary information of
* Day Management AG, ("Confidential Information"). You shall not
* disclose such Confidential Information and shall use it only in
* accordance with the terms of the license agreement you entered into
* with Day.
*/
package com.day.cq.commons;
import java.util.List;
import java.util.ArrayList;
import org.apache.jackrabbit.util.Text;
/**
* Implements a version.
*/
public class Version implements Comparable {
/**
* The empty version
*/
public static final Version EMPTY = new Version("", new String[0]);
/**
* internal string representation
*/
private final String str;
/**
* All segments of this version
*/
private final String[] segments;
/**
* Creates a new version from the given string.
* @param str the version string.
* @return the new version or {@link Version#EMPTY} if str is an empty string.
*/
public static Version create(String str) {
if (str == null || str.length() == 0) {
return Version.EMPTY;
}else {
return new Version(str, Text.explode(str, '.'));
}
}
/**
* Creates a new version from version segments
* @param segments version segments
* @return the new version or {@link Version#EMPTY} if segments is empty.
*/
public static Version create(String[] segments) {
if (segments == null || segments.length == 0) {
return Version.EMPTY;
} else {
return new Version(Text.implode(segments, "."), segments);
}
}
/**
* Internal constructor
* @param str string
* @param segments segments
*/
private Version(String str, String[] segments) {
if (str == null) {
throw new NullPointerException("Version String must not be null.");
}
this.str = str;
List list = new ArrayList();
for (String seg: segments) {
for (String sub: Text.explode(seg, '-')) {
list.add(sub);
}
}
this.segments = list.toArray(new String[list.size()]);
}
@Override
public int hashCode() {
return str.hashCode();
}
@Override
public boolean equals(Object o) {
return this == o ||
o instanceof Version && str.equals(((Version) o).str);
}
@Override
public String toString() {
return str;
}
/**
* Returns all segments.
* @return all segments.
*/
public String[] getNormalizedSegments() {
return segments;
}
/**
* Compares this version to the given one, segment by segment with a special
* "SNAPSHOT" handling.
*
* Examples:
* "1" < "2"
* "1.0" < "2"
* "2.0.1" < "2.1"
* "2.1" < "2.1.1"
* "2.1" < "2.1-SNAPSHOT"
* "2.1" < "2.1-R1234556"
* "2.1-R12345" < "2.1-SNAPSHOT"
*
* @param o the other version
* @return a negative integer, zero, or a positive integer as this version
* is less than, equal to, or greater than the specified version.
*/
public int compareTo(Version o) {
String[] oSegs = o.getNormalizedSegments();
for (int i=0; i< Math.min(segments.length, oSegs.length); i++) {
int comp = segments[i].compareTo(oSegs[i]);
if (comp != 0) {
return comp;
}
}
return segments.length - oSegs.length;
}
}