opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/impl/util/ClassLoaderUtils.java

   1 package org.opendaylight.controller.sal.binding.impl.util;
   2
   3
   4
   5 import java.util.concurrent.Callable;
   6 import java.util.concurrent.locks.Lock;
   7
   8 import static com.google.common.base.Preconditions.*;
   9
  10 import java.lang.reflect.Constructor;
  11 import java.lang.reflect.InvocationTargetException;
  12 import java.util.ArrayList;
  13
  14 import com.google.common.base.Optional;
  15
  16 public class ClassLoaderUtils {
  17
  18     public static <V> V withClassLoader(ClassLoader cls,Callable<V> function) throws Exception {
  19         return withClassLoaderAndLock(cls, Optional.<Lock>absent(), function);
  20     }
  21
  22     public static <V> V withClassLoaderAndLock(ClassLoader cls,Lock lock,Callable<V> function) throws Exception {
  23         checkNotNull(lock,"Lock should not be null");
  24         return withClassLoaderAndLock(cls, Optional.of(lock), function);
  25     }
  26
  27     public static <V> V withClassLoaderAndLock(ClassLoader cls,Optional<Lock> lock,Callable<V> function) throws Exception {
  28         checkNotNull(cls, "Classloader should not be null");
  29         checkNotNull(function,"Function should not be null");
  30         if(lock.isPresent()) {
  31             lock.get().lock();
  32         }
  33         ClassLoader oldCls = Thread.currentThread().getContextClassLoader();
  34         try {
  35             Thread.currentThread().setContextClassLoader(cls);
  36             V result = function.call();
  37             return result;
  38         }  finally {
  39             Thread.currentThread().setContextClassLoader(oldCls);
  40             if(lock.isPresent()) {
  41                 lock.get().unlock();
  42             }
  43         }
  44     }
  45
  46     public static Object construct(Constructor<? extends Object> constructor, ArrayList<Object> objects) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
  47     Object[] initargs = objects.toArray(new Object[]{});
  48     return constructor.newInstance(initargs);
  49     }
  50
  51
  52     public static Class<?> loadClassWithTCCL(String name) throws ClassNotFoundException {
  53         if("byte[]".equals(name)) {
  54             return byte[].class;
  55         }
  56
  57         return Thread.currentThread().getContextClassLoader().loadClass(name);
  58     }
  59 }