org.apache.aries.proxy.impl.ProxyUtils.java Source code

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Here is the source code for org.apache.aries.proxy.impl.ProxyUtils.java

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/*
 * 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.
 */
package org.apache.aries.proxy.impl;

import java.math.BigDecimal;

import org.objectweb.asm.Opcodes;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ProxyUtils {
    private static Logger LOGGER = LoggerFactory.getLogger(ProxyUtils.class);
    public static final int JAVA_CLASS_VERSION = new BigDecimal(System.getProperty("java.class.version"))
            .intValue();
    private static int weavingJavaVersion = -1; // initialise an invalid number

    /**
     * Get the java version to be woven at.
     * @return
     */
    public static int getWeavingJavaVersion() {
        if (weavingJavaVersion == -1) {
            //In order to avoid an inconsistent stack error the version of the woven byte code needs to match
            //the level of byte codes in the original class
            switch (JAVA_CLASS_VERSION) {
            case Opcodes.V1_8:
                LOGGER.debug("Weaving to Java 8");
                weavingJavaVersion = Opcodes.V1_8;
                break;
            case Opcodes.V1_7:
                LOGGER.debug("Weaving to Java 7");
                weavingJavaVersion = Opcodes.V1_7;
                break;
            case Opcodes.V1_6:
                LOGGER.debug("Weaving to Java 6");
                weavingJavaVersion = Opcodes.V1_6;
                break;
            case Opcodes.V1_5:
                LOGGER.debug("Weaving to Java 5");
                weavingJavaVersion = Opcodes.V1_5;
                break;
            default:
                //aries should work with Java 5 or above - also will highlight when a higher level (and unsupported) level of Java is released
                throw new IllegalArgumentException("Invalid Java version " + JAVA_CLASS_VERSION);
            }
        }
        return weavingJavaVersion;
    }
}