/*
*
* 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.flex.utils;
/**
* Represents a four-part version number, such as <code>4.5.12.12345</code>.
* <p>
* The second, third, and fourth parts, representing a minor version,
* a bug-fix version, and a build version, are optional.
* When comparing versions, a missing part is considered to be 0.
*/
public class Version implements Comparable<Version>
{
/**
* Compares two possibly-null Integer values,
* considering a null Integer to be 0.
*/
private static int cmp(Integer i1, Integer i2)
{
// For comparison purposes, consider a null Integer to be 0.
int j1 = i1 != null ? i1 : 0;
int j2 = i2 != null ? i2 : 0;
if (j1 > j2)
return 1;
else if (j1 < j2)
return -1;
return 0;
}
/**
* Constructs a new <code>Version</code> instance with all four parts.
*
* @param major The major version number.
* @param minor The minor version number.
* @param bugFix The bug-fix version number.
* @param build The build version number or <code>null</code>.
*/
public Version(Integer major, Integer minor, Integer bugFix, Integer build)
{
assert major >= 0 : "major version number cannot be negative";
assert minor == null || minor >= 0 : "minor version number cannot be negative";
assert bugFix == null || bugFix >= 0 : "bugFix version number cannot be negative";
assert build == null || build >= 0 : "build version number cannot be negative";
this.major = major;
this.minor = minor;
this.bugFix = bugFix;
this.build = build;
}
/**
* Constructs a new <code>Version</code> instance with three parts.
*
* @param major The major version number.
* @param minor The minor version number or <code>null</code>.
* @param bugFix The bug-fix version number or <code>null</code>.
*/
public Version(int major, int minor, int bugFix)
{
this(major, minor, bugFix, null);
}
/**
* Constructs a new <code>Version</code> instance with two parts.
*
* @param major The major version number.
* @param minor The minor version number or <code>null</code>.
*/
public Version(int major, int minor)
{
this(major, minor, null, null);
}
/**
* Constructs a new <code>Version</code> instance with one part.
*
* @param major The major version number.
*/
public Version(int major)
{
this(major, null, null, null);
}
/**
* Constructs a new <code>Version</code> instance from a
* one-, two-, three-, or four-part dotted version string.
*/
public Version(String versionString)
{
this(versionString.split("\\."));
}
private Version(String[] parts)
{
int n = parts.length;
assert 1 <= n && n <= 4 : "version string should have 1-4 parts";
this.major = Integer.parseInt(parts[0]);
this.minor = n >= 2 ? Integer.parseInt(parts[1]) : null;
this.bugFix = n >= 3 ? Integer.parseInt(parts[2]) : null;
this.build = n == 4 ? Integer.parseInt(parts[3]) : null;
}
private final Integer major;
private final Integer minor;
private final Integer bugFix;
private final Integer build;
@Override
public String toString()
{
return getDisplayString();
}
@Override
public int compareTo(Version other)
{
int compareBugFix = compareBugFixVersionTo(other);
if (compareBugFix != 0)
return compareBugFix;
return cmp(build, other.build);
}
/**
* Gets the major version number.
*
* @return An <code>Integer</code> for the major version.
*/
public Integer getMajor()
{
return major;
}
/**
* Gets the minor version number number.
*
* @return An <code>Integer</code> for the minor version or <code>null</code>.
*/
public Integer getMinor()
{
return minor;
}
/**
* Gets the bug-fix version number.
*
* @return An <code>Integer</code> for the bug-fix version or <code>null</code>.
*/
public Integer getBugFix()
{
return bugFix;
}
/**
* Gets the build version number.
*
* @return An <code>Integer</code> for the build version or <code>null</code>.
*/
public Integer getBuild()
{
return build;
}
/**
* Converts this <code>Version<code> to a string for display.
* <p>
* Null parts of the version are not displayed.
*
* @return A String such as <code>"1.2"</code>.
*/
public String getDisplayString()
{
StringBuilder sb = new StringBuilder();
sb.append(major);
if (minor != null)
{
sb.append('.');
sb.append(minor);
}
if (bugFix != null)
{
sb.append('.');
sb.append(bugFix);
}
if (build != null)
{
sb.append('.');
sb.append(build);
}
return sb.toString();
}
/**
* Compares this <code>Version</code> to another,
* considering only the major part.
*
* @param other Another <code>Version</code> object.
* @return 1 if greater, -1 if lesser, 0 if equal
*/
public int compareMajorVersionTo(Version other)
{
return cmp(major, other.major);
}
/**
* Compares this <code>Version</code> to another,
* considering only the major and minor parts.
*
* @param other Another <code>Version</code> object.
* @return 1 if greater, -1 if lesser, 0 if equal
*/
public int compareMinorVersionTo(Version other)
{
int compareMajor = compareMajorVersionTo(other);
if (compareMajor != 0)
return compareMajor;
return cmp(minor, other.minor);
}
/**
* Compares this <code>Version</code> to another,
* considering only the major, minor, and bug-fix parts.
*
* @param other Another <code>Version</code> object.
* @return 1 if greater, -1 if lesser, 0 if equal
*/
public int compareBugFixVersionTo(Version other)
{
int compareMinor = compareMinorVersionTo(other);
if (compareMinor != 0)
return compareMinor;
return cmp(bugFix, other.bugFix);
}
}