lodsve.core.condition.ConditionalOnJava Maven / Gradle / Ivy
/*
* Copyright 2012-2015 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
*
* 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 lodsve.core.condition;
import org.springframework.context.annotation.Conditional;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* {@link Conditional} that matches based on the JVM version the application is running
* on.
*
* @author Oliver Gierke
* @author Phillip Webb
* @author Andy Wilkinson
* @since 1.1.0
*/
@Target({ ElementType.TYPE, ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Conditional(OnJavaCondition.class)
public @interface ConditionalOnJava {
/**
* Configures whether the value configured in {@link #value()} shall be considered the
* upper exclusive or lower inclusive boundary. Defaults to
* {@link Range#EQUAL_OR_NEWER}.
* @return the range
*/
Range range() default Range.EQUAL_OR_NEWER;
/**
* The {@link JavaVersion} to check for. Use {@link #range()} to specify whether the
* configured value is an upper-exclusive or lower-inclusive boundary.
* @return the java version
*/
JavaVersion value();
/**
* Range options.
*/
enum Range {
/**
* Equal to, or newer than the specified {@link JavaVersion}.
*/
EQUAL_OR_NEWER,
/**
* Older than the specified {@link JavaVersion}.
*/
OLDER_THAN
}
/**
* Java versions.
*/
enum JavaVersion {
/**
* Java 1.9.
*/
NINE(9, "1.9", "java.security.cert.URICertStoreParameters"),
/**
* Java 1.8.
*/
EIGHT(8, "1.8", "java.util.function.Function"),
/**
* Java 1.7.
*/
SEVEN(7, "1.7", "java.nio.file.Files"),
/**
* Java 1.6.
*/
SIX(6, "1.6", "java.util.ServiceLoader");
private final int value;
private final String name;
private final boolean available;
JavaVersion(int value, String name, String className) {
this.value = value;
this.name = name;
this.available = ClassUtils.isPresent(className, getClass().getClassLoader());
}
/**
* Determines if this version is within the specified range of versions.
* @param range the range
* @param version the bounds of the range
* @return if this version is within the specified range
*/
public boolean isWithin(Range range, JavaVersion version) {
Assert.notNull(range, "Range must not be null");
Assert.notNull(version, "Version must not be null");
switch (range) {
case EQUAL_OR_NEWER:
return this.value >= version.value;
case OLDER_THAN:
return this.value < version.value;
}
throw new IllegalStateException("Unknown range " + range);
}
@Override
public String toString() {
return this.name;
}
/**
* Returns the {@link JavaVersion} of the current runtime.
* @return the {@link JavaVersion}
*/
public static JavaVersion getJavaVersion() {
for (JavaVersion candidate : JavaVersion.values()) {
if (candidate.available) {
return candidate;
}
}
return SIX;
}
}
}