org.springframework.boot.system.JavaVersion Maven / Gradle / Ivy
/*
* Copyright 2012-2020 the original author or authors.
*
* 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
*
* https://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.springframework.boot.system;
import java.lang.invoke.MethodHandles;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Optional;
import java.util.stream.Stream;
import org.springframework.util.ClassUtils;
/**
* Known Java versions.
*
* @author Oliver Gierke
* @author Phillip Webb
* @since 2.0.0
*/
public enum JavaVersion {
/**
* Java 1.8.
*/
EIGHT("1.8", Optional.class, "empty"),
/**
* Java 9.
*/
NINE("9", Optional.class, "stream"),
/**
* Java 10.
*/
TEN("10", Optional.class, "orElseThrow"),
/**
* Java 11.
*/
ELEVEN("11", String.class, "strip"),
/**
* Java 12.
*/
TWELVE("12", String.class, "describeConstable"),
/**
* Java 13.
*/
THIRTEEN("13", String.class, "stripIndent"),
/**
* Java 14.
*/
FOURTEEN("14", MethodHandles.Lookup.class, "hasFullPrivilegeAccess"),
/**
* Java 15.
*/
FIFTEEN("15", CharSequence.class, "isEmpty"),
/**
* Java 16.
*/
SIXTEEN("16", Stream.class, "toList");
private final String name;
private final boolean available;
JavaVersion(String name, Class clazz, String methodName) {
this.name = name;
this.available = ClassUtils.hasMethod(clazz, methodName);
}
@Override
public String toString() {
return this.name;
}
/**
* Returns the {@link JavaVersion} of the current runtime.
* @return the {@link JavaVersion}
*/
public static JavaVersion getJavaVersion() {
List candidates = Arrays.asList(JavaVersion.values());
Collections.reverse(candidates);
for (JavaVersion candidate : candidates) {
if (candidate.available) {
return candidate;
}
}
return EIGHT;
}
/**
* Return if this version is equal to or newer than a given version.
* @param version the version to compare
* @return {@code true} if this version is equal to or newer than {@code version}
*/
public boolean isEqualOrNewerThan(JavaVersion version) {
return compareTo(version) >= 0;
}
/**
* Return if this version is older than a given version.
* @param version the version to compare
* @return {@code true} if this version is older than {@code version}
*/
public boolean isOlderThan(JavaVersion version) {
return compareTo(version) < 0;
}
}