/*
* Copyright 2015-2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file 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 com.amazonaws.util;
import java.util.Arrays;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* @see http://www.oracle.com/technetwork/java/javase/versioning-naming-139433.html
*/
public class JavaVersionParser {
public static final String JAVA_VERSION_PROPERTY = "java.version";
private static String MAJOR_VERSION_FAMILY_PATTERN = "\\d+";
private static String MAJOR_VERSION_PATTERN = "\\d+";
private static String MAINTENANCE_NUMBER_PATTERN = "\\d+";
private static String UPDATE_NUMBER_PATTERN = "\\d+";
private static Pattern VERSION_REGEX = Pattern.compile(String.format("(%s)\\.(%s)\\.(%s)(?:_(%s))?.*",
MAJOR_VERSION_FAMILY_PATTERN, MAJOR_VERSION_PATTERN, MAINTENANCE_NUMBER_PATTERN, UPDATE_NUMBER_PATTERN));
private static final JavaVersion currentJavaVersion = parseJavaVersion(System.getProperty(JAVA_VERSION_PROPERTY));
private JavaVersionParser() {
}
/**
* @return The {@link JavaVersion} of this JVM.
*/
public static JavaVersion getCurrentJavaVersion() {
return currentJavaVersion;
}
public static JavaVersion parseJavaVersion(final String fullVersionString) {
if (!StringUtils.isNullOrEmpty(fullVersionString)) {
final Matcher matcher = VERSION_REGEX.matcher(fullVersionString);
if (matcher.matches()) {
final Integer majorVersionFamily = NumberUtils.tryParseInt(matcher.group(1));
final Integer majorVersion = NumberUtils.tryParseInt(matcher.group(2));
final Integer maintenanceNumber = NumberUtils.tryParseInt(matcher.group(3));
final Integer updateNumber = NumberUtils.tryParseInt(matcher.group(4));
return new JavaVersion(majorVersionFamily, majorVersion, maintenanceNumber, updateNumber);
}
}
return JavaVersion.UNKNOWN;
}
/**
* Struct like class representing a specific version of Java. Contains the major and minor
* version identifiers and a descriptive enum identifying which major version this JVM belongs
* to if we are able to identify it
*/
public static final class JavaVersion implements Comparable<JavaVersion> {
public static final JavaVersionParser.JavaVersion UNKNOWN = new JavaVersionParser.JavaVersion(null, null, null,
null);
private final Integer[] tokenizedVersion;
private final Integer majorVersionFamily;
private final Integer majorVersion;
private final Integer maintenanceNumber;
private final Integer updateNumber;
private final KnownJavaVersions knownVersion;
public JavaVersion(final Integer majorVersionFamily, final Integer majorVersion,
final Integer maintenanceNumber, final Integer updateNumber) {
this.majorVersionFamily = majorVersionFamily;
this.majorVersion = majorVersion;
this.maintenanceNumber = maintenanceNumber;
this.updateNumber = updateNumber;
this.knownVersion = KnownJavaVersions.fromMajorVersion(majorVersionFamily, majorVersion);
this.tokenizedVersion = this.getTokenizedVersion();
}
private Integer[] getTokenizedVersion() {
return new Integer[] { this.majorVersionFamily, this.majorVersion, this.maintenanceNumber,
this.updateNumber };
}
/**
* @return Major version family if available. I.E. if the major version family string is
* '1.7.0_60' then the major version family will be 1
*/
public Integer getMajorVersionFamily() {
return this.majorVersionFamily;
}
/**
* @return Major version ordinal if available. Examples include '6', '7', '8'
*/
public Integer getMajorVersion() {
return this.majorVersion;
}
/**
* @return Major version string if available. Examples include '1.6', '1.7', '1.8'
*/
public String getMajorVersionString() {
return String.format("%d.%d", this.majorVersionFamily, this.majorVersion);
}
/**
* @return Maintenance number of Java version. If the version is '1.6.1_20' then '1' is the
* maintenance number
*/
public Integer getMaintenanceNumber() {
return this.maintenanceNumber;
}
/**
* @return Update number of Java version. If the version is '1.6.1_20' then '20' is the
* update number
*/
public Integer getUpdateNumber() {
return this.updateNumber;
}
/**
* @return {@link KnownJavaVersions} representing the major version of the Java version if
* it's identifiable
*/
public KnownJavaVersions getKnownVersion() {
return this.knownVersion;
}
@Override
public int compareTo(final JavaVersion other) {
for (int i = 0; i < this.tokenizedVersion.length; i++) {
final int tokenComparison = ComparableUtils.safeCompare(this.tokenizedVersion[i],
other.tokenizedVersion[i]);
// If one token is larger return the comparison otherwise proceed to next token
if (tokenComparison != 0) {
return tokenComparison;
}
}
return 0;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = (prime * result) + ((this.knownVersion == null) ? 0 : this.knownVersion.hashCode());
result = (prime * result) + ((this.maintenanceNumber == null) ? 0 : this.maintenanceNumber.hashCode());
result = (prime * result) + ((this.majorVersion == null) ? 0 : this.majorVersion.hashCode());
result = (prime * result) + ((this.majorVersionFamily == null) ? 0 : this.majorVersionFamily.hashCode());
result = (prime * result) + Arrays.hashCode(this.tokenizedVersion);
result = (prime * result) + ((this.updateNumber == null) ? 0 : this.updateNumber.hashCode());
return result;
}
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (this.getClass() != obj.getClass()) {
return false;
}
final JavaVersion other = (JavaVersion) obj;
if (this.knownVersion != other.knownVersion) {
return false;
}
if (this.maintenanceNumber == null) {
if (other.maintenanceNumber != null) {
return false;
}
} else if (!this.maintenanceNumber.equals(other.maintenanceNumber)) {
return false;
}
if (this.majorVersion == null) {
if (other.majorVersion != null) {
return false;
}
} else if (!this.majorVersion.equals(other.majorVersion)) {
return false;
}
if (this.majorVersionFamily == null) {
if (other.majorVersionFamily != null) {
return false;
}
} else if (!this.majorVersionFamily.equals(other.majorVersionFamily)) {
return false;
}
if (!Arrays.equals(this.tokenizedVersion, other.tokenizedVersion)) {
return false;
}
if (this.updateNumber == null) {
if (other.updateNumber != null) {
return false;
}
} else if (!this.updateNumber.equals(other.updateNumber)) {
return false;
}
return true;
}
}
/**
* Enum representing all the Java versions we know about and a special enum value
* {@link KnownJavaVersions#UNKNOWN} for ones we don't yet know about
*/
public enum KnownJavaVersions {
JAVA_6(1, 6),
JAVA_7(1, 7),
JAVA_8(1, 8),
JAVA_9(1, 9),
UNKNOWN(0, -1);
private Integer knownMajorVersionFamily;
private Integer knownMajorVersion;
private KnownJavaVersions(final int majorVersionFamily, final int majorVersion) {
this.knownMajorVersionFamily = majorVersionFamily;
this.knownMajorVersion = Integer.valueOf(majorVersion);
}
/**
* Tries to determine a known version from the parsed major version components
*
* @param majorVersionFamily
* Major version family of the JVM. Currently only 1 is known (i.e. '1.7')
* @param majorVersion
* Major version of JVM (6, 7, 8, etc)
* @return A {@link KnownJavaVersions} or {@link KnownJavaVersions#UNKNOWN} if unable to
* determine
*/
public static KnownJavaVersions fromMajorVersion(final Integer majorVersionFamily, final Integer majorVersion) {
for (final KnownJavaVersions version : KnownJavaVersions.values()) {
if (version.isMajorVersion(majorVersionFamily, majorVersion)) {
return version;
}
}
return UNKNOWN;
}
/**
* @param majorVersionFamily
* Major version family of the JVM. Currently only 1 is known (i.e. '1.7')
* @param majorVersion
* Major version of JVM (6, 7, 8, etc)
* @return True if the major version is applicable to this Java Version
*/
private boolean isMajorVersion(final Integer majorVersionFamily, final Integer majorVersion) {
return this.knownMajorVersionFamily.equals(majorVersionFamily)
&& this.knownMajorVersion.equals(majorVersion);
}
}
}