aQute.bnd.version.ComparableVersion Maven / Gradle / Ivy
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package aQute.bnd.version;
/*
* 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.
*/
import java.math.BigInteger;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Deque;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
/**
*
* Generic implementation of version comparison.
*
* Features:
*
* - mixing of '
-' (hyphen) and '.' (dot)
* separators,
* - transition between characters and digits also constitutes a separator:
*
1.0alpha1 => [1, 0, alpha, 1]
* - unlimited number of version components,
* - version components in the text can be digits or strings,
* - strings are checked for well-known qualifiers and the qualifier ordering
* is used for version ordering. Well-known qualifiers (case insensitive) are:
*
* alpha or abeta or bmilestone or mrc or crsnapshot(the empty string) or ga or
* finalsp
* Unknown qualifiers are considered after known qualifiers, with lexical order
* (always case insensitive),
* - a hyphen usually precedes a qualifier, and is always less important than
* something preceded with a dot.
*
*
* @see "Versioning"
* on Maven Wiki
* @author Kenney Westerhof
* @author Hervé Boutemy
*/
class ComparableVersion implements Comparable {
private static final ComparableVersion empty = new ComparableVersion("");
private final String value;
private final String canonical;
private final 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 BIG_INTEGER_ZERO = new BigInteger("0");
private final BigInteger value;
public static final IntegerItem ZERO = new IntegerItem();
private IntegerItem() {
this.value = BIG_INTEGER_ZERO;
}
IntegerItem(String str) {
this.value = new BigInteger(str);
}
@Override
public int getType() {
return INTEGER_ITEM;
}
@Override
public boolean isNull() {
return BIG_INTEGER_ZERO.equals(value);
}
@Override
public int compareTo(Item item) {
if (item == null) {
return BIG_INTEGER_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());
}
}
@Override
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 _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 final String value;
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;
default :
}
}
this.value = ALIASES.getProperty(value, value);
}
@Override
public int getType() {
return STRING_ITEM;
}
@Override
public boolean isNull() {
return (comparableQualifier(value).compareTo(RELEASE_VERSION_INDEX) == 0);
}
/**
* Returns a comparable value for a qualifier. This method takes into
* account the ordering of known qualifiers then unknown qualifiers with
* lexical ordering. 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
* @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- implements Item {
private static final long serialVersionUID = 1L;
ListItem() {}
@Override
public int getType() {
return LIST_ITEM;
}
@Override
public boolean isNull() {
return (size() == 0);
}
void normalize() {
for (int i = size() - 1; i >= 0; i--) {
Item lastItem = get(i);
if (lastItem.isNull()) {
// remove null trailing items: 0, "", empty list
remove(i);
} else if (!(lastItem instanceof ListItem)) {
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
- left = iterator();
Iterator
- right = ((ListItem) item).iterator();
while (left.hasNext() || right.hasNext()) {
Item l = left.hasNext() ? left.next() : null;
Item r = right.hasNext() ? right.next() : null;
// if this is shorter, then invert the compare and mul
// with -1
int result = l == null ? (r == null ? 0 : -1 * r.compareTo(l)) : l.compareTo(r);
if (result != 0) {
return result;
}
}
return 0;
default :
throw new RuntimeException("invalid item: " + item.getClass());
}
}
@Override
public String toString() {
StringBuilder buffer = new StringBuilder();
for (Item item : this) {
if (buffer.length() > 0) {
buffer.append((item instanceof ListItem) ? '-' : '.');
}
buffer.append(item);
}
return buffer.toString();
}
}
static ComparableVersion parseVersion(String version) {
if (version == null) {
return empty;
}
return new ComparableVersion(version);
}
private ComparableVersion(String version) {
this.value = version;
items = new ListItem();
version = version.toLowerCase(Locale.ENGLISH);
ListItem list = items;
Deque
stack = new ArrayDeque<>();
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;
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;
list.add(list = new ListItem());
stack.push(list);
}
isDigit = true;
} else {
if (isDigit && i > startIndex) {
list.add(parseItem(true, version.substring(startIndex, i)));
startIndex = i;
list.add(list = new ListItem());
stack.push(list);
}
isDigit = false;
}
}
if (version.length() > startIndex) {
list.add(parseItem(isDigit, version.substring(startIndex)));
}
while (!stack.isEmpty()) {
list = 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 instanceof ComparableVersion) && canonical.equals(((ComparableVersion) o).canonical);
}
@Override
public int hashCode() {
return canonical.hashCode();
}
}