/*
* #%L
* Wisdom-Framework
* %%
* Copyright (C) 2013 - 2014 Wisdom Framework
* %%
* 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.
* #L%
*/
package org.wisdom.resources;
import java.math.BigInteger;
import java.util.*;
/**
* Code source of this file from:
* https://maven.apache.org/ref/3.2.1/maven-artifact/apidocs/src-html/org/apache/maven/artifact/versioning/ComparableVersion.html
* Maven-artifact
* + package org.apache.maven.artifact.versioning
*/
/**
* Generic implementation of version comparison.
* <p/>
* <p>Features:
* <ul>
* <li>mixing of '<code>-</code>' (dash) and '<code>.</code>' (dot) separators,</li>
* <li>transition between characters and digits also constitutes a separator:
* <code>1.0alpha1 => [1, 0, alpha, 1]</code></li>
* <li>unlimited number of version components,</li>
* <li>version components in the text can be digits or strings,</li>
* <li>strings are checked for well-known qualifiers and the qualifier ordering is used for version ordering.
* Well-known qualifiers (case insensitive) are:<ul>
* <li><code>snapshot</code></li>
* <li><code>alpha</code> or <code>a</code></li>
* <li><code>beta</code> or <code>b</code></li>
* <li><code>milestone</code> or <code>m</code></li>
* <li><code>rc</code> or <code>cr</code></li>
* <li><code>(the empty string)</code> or <code>ga</code> or <code>final</code></li>
* <li><code>sp</code></li>
* </ul>
* Unknown qualifiers are considered after known qualifiers, with lexical order (always case insensitive),
* </li>
* <li>a dash usually precedes a qualifier, and is always less important than something preceded with a dot.</li>
* </ul></p>
*
* @author <a href="mailto:kenney@apache.org">Kenney Westerhof</a>
* @author <a href="mailto:hboutemy@apache.org">Hervé Boutemy</a>
* @see <a href="https://cwiki.apache.org/confluence/display/MAVENOLD/Versioning">"Versioning" on Maven Wiki</a>
*/
public class ComparableVersion
implements Comparable<ComparableVersion> {
private String value;
private String canonical;
private ListItem items;
private interface Item {
int INTEGER_ITEM = 0;
int STRING_ITEM = 1;
int LIST_ITEM = 2;
int compareTo(Item item);
int getType();
boolean isNull();
}
/**
* Represents a numeric item in the version item list.
*/
private static class IntegerItem
implements Item {
private static final BigInteger BigInteger_ZERO = new BigInteger("0");
private final BigInteger value;
public static final IntegerItem ZERO = new IntegerItem();
private IntegerItem() {
this.value = BigInteger_ZERO;
}
public IntegerItem(String str) {
this.value = new BigInteger(str);
}
public int getType() {
return INTEGER_ITEM;
}
public boolean isNull() {
return BigInteger_ZERO.equals(value);
}
public int compareTo(Item item) {
if (item == null) {
return BigInteger_ZERO.equals(value) ? 0 : 1; // 1.0 == 1, 1.1 > 1
}
switch (item.getType()) {
case INTEGER_ITEM:
return value.compareTo(((IntegerItem) item).value);
case STRING_ITEM:
return 1; // 1.1 > 1-sp
case LIST_ITEM:
return 1; // 1.1 > 1-1
default:
throw new RuntimeException("invalid item: " + item.getClass());
}
}
public String toString() {
return value.toString();
}
}
/**
* Represents a string in the version item list, usually a qualifier.
*/
private static class StringItem
implements Item {
private static final String[] QUALIFIERS = {"alpha", "beta", "milestone", "rc", "snapshot", "", "sp"};
private static final List<String> _QUALIFIERS = Arrays.asList(QUALIFIERS);
private static final Properties ALIASES = new Properties();
static {
ALIASES.put("ga", "");
ALIASES.put("final", "");
ALIASES.put("cr", "rc");
}
/**
* A comparable value for the empty-string qualifier. This one is used to determine if a given qualifier makes
* the version older than one without a qualifier, or more recent.
*/
private static final String RELEASE_VERSION_INDEX = String.valueOf(_QUALIFIERS.indexOf(""));
private String value;
public StringItem(String value, boolean followedByDigit) {
if (followedByDigit && value.length() == 1) {
// a1 = alpha-1, b1 = beta-1, m1 = milestone-1
switch (value.charAt(0)) {
case 'a':
value = "alpha";
break;
case 'b':
value = "beta";
break;
case 'm':
value = "milestone";
break;
}
}
this.value = ALIASES.getProperty(value, value);
}
/**
* @return the type.
*/
public int getType() {
return STRING_ITEM;
}
public boolean isNull() {
return (comparableQualifier(value).compareTo(RELEASE_VERSION_INDEX) == 0);
}
/**
* Returns a comparable value for a qualifier.
* <p/>
* This method takes into account the ordering of known qualifiers then unknown qualifiers with lexical ordering.
* <p/>
* just returning an Integer with the index here is faster, but requires a lot of if/then/else to check for -1
* or QUALIFIERS.size and then resort to lexical ordering. Most comparisons are decided by the first character,
* so this is still fast. If more characters are needed then it requires a lexical sort anyway.
*
* @param qualifier the qualifier
* @return an equivalent value that can be used with lexical comparison
*/
public static String comparableQualifier(String qualifier) {
int i = _QUALIFIERS.indexOf(qualifier);
return i == -1 ? (_QUALIFIERS.size() + "-" + qualifier) : String.valueOf(i);
}
@Override
public int compareTo(Item item) {
if (item == null) {
// 1-rc < 1, 1-ga > 1
return comparableQualifier(value).compareTo(RELEASE_VERSION_INDEX);
}
switch (item.getType()) {
case INTEGER_ITEM:
return -1; // 1.any < 1.1 ?
case STRING_ITEM:
return comparableQualifier(value).compareTo(comparableQualifier(((StringItem) item).value));
case LIST_ITEM:
return -1; // 1.any < 1-1
default:
throw new RuntimeException("invalid item: " + item.getClass());
}
}
@Override
public String toString() {
return value;
}
}
/**
* Represents a version list item. This class is used both for the global item list and for sub-lists (which start
* with '-(number)' in the version specification).
*/
private static class ListItem
extends ArrayList<Item>
implements Item {
/**
* @return the instance type.
*/
public int getType() {
return LIST_ITEM;
}
/**
* @return whether or not the syze is 0.
*/
public boolean isNull() {
return (size() == 0);
}
void normalize() {
for (ListIterator<Item> iterator = listIterator(size()); iterator.hasPrevious(); ) {
Item item = iterator.previous();
if (item.isNull()) {
iterator.remove(); // remove null trailing items: 0, "", empty list
} else {
break;
}
}
}
@Override
public int compareTo(Item item) {
if (item == null) {
if (size() == 0) {
return 0; // 1-0 = 1- (normalize) = 1
}
Item first = get(0);
return first.compareTo(null);
}
switch (item.getType()) {
case INTEGER_ITEM:
return -1; // 1-1 < 1.0.x
case STRING_ITEM:
return 1; // 1-1 > 1-sp
case LIST_ITEM:
Iterator<Item> left = iterator();
Iterator<Item> right = ((ListItem) item).iterator();
while (left.hasNext() || right.hasNext()) {
Item l = left.hasNext() ? left.next() : null;
Item r = right.hasNext() ? right.next() : null;
if (l == null && r == null) {
return 0;
}
int result;
if (r != null) {
result = -1 * r.compareTo(l);
} else {
result = l.compareTo(null);
}
if (result != 0) {
return result;
}
}
return 0;
default:
throw new RuntimeException("invalid item: " + item.getClass());
}
}
@Override
public String toString() {
StringBuilder buffer = new StringBuilder("(");
for (Iterator<Item> iter = iterator(); iter.hasNext(); ) {
buffer.append(iter.next());
if (iter.hasNext()) {
buffer.append(',');
}
}
buffer.append(')');
return buffer.toString();
}
}
/**
* Creates a new instance of {@link ComparableVersion}.
*
* @param version the version that will be parsed
*/
public ComparableVersion(String version) {
parseVersion(version);
}
/**
* Parses the version
*
* @param version the version
*/
public final void parseVersion(String version) {
this.value = version;
items = new ListItem();
version = version.toLowerCase(Locale.ENGLISH);
ListItem list = items;
Stack<Item> stack = new Stack<Item>();
stack.push(list);
boolean isDigit = false;
int startIndex = 0;
for (int i = 0; i < version.length(); i++) {
char c = version.charAt(i);
if (c == '.') {
if (i == startIndex) {
list.add(IntegerItem.ZERO);
} else {
list.add(parseItem(isDigit, version.substring(startIndex, i)));
}
startIndex = i + 1;
} else if (c == '-') {
if (i == startIndex) {
list.add(IntegerItem.ZERO);
} else {
list.add(parseItem(isDigit, version.substring(startIndex, i)));
}
startIndex = i + 1;
if (isDigit) {
list.normalize(); // 1.0-* = 1-*
if ((i + 1 < version.length()) && Character.isDigit(version.charAt(i + 1))) {
// new ListItem only if previous were digits and new char is a digit,
// ie need to differentiate only 1.1 from 1-1
list.add(list = new ListItem());
stack.push(list);
}
}
} else if (Character.isDigit(c)) {
if (!isDigit && i > startIndex) {
list.add(new StringItem(version.substring(startIndex, i), true));
startIndex = i;
}
isDigit = true;
} else {
if (isDigit && i > startIndex) {
list.add(parseItem(true, version.substring(startIndex, i)));
startIndex = i;
}
isDigit = false;
}
}
if (version.length() > startIndex) {
list.add(parseItem(isDigit, version.substring(startIndex)));
}
while (!stack.isEmpty()) {
list = (ListItem) stack.pop();
list.normalize();
}
canonical = items.toString();
}
private static Item parseItem(boolean isDigit, String buf) {
return isDigit ? new IntegerItem(buf) : new StringItem(buf, false);
}
@Override
public int compareTo(ComparableVersion o) {
return items.compareTo(o.items);
}
@Override
public String toString() {
return value;
}
@Override
public boolean equals(Object o) {
return (o != null && o.getClass() == this.getClass()) && canonical.equals(((ComparableVersion) o).canonical);
}
@Override
public int hashCode() {
return canonical.hashCode();
}
}