Example usage for org.apache.commons.lang3.reflect ConstructorUtils getAccessibleConstructor

Introduction

In this page you can find the example usage for org.apache.commons.lang3.reflect ConstructorUtils getAccessibleConstructor.

Prototype

public static <T> Constructor<T> getAccessibleConstructor(final Constructor<T> ctor) 

Source Link

Document

Checks if the specified constructor is accessible.

This simply ensures that the constructor is accessible.

Usage

From source file:com.robertsmieja.test.utils.junit.Internal.java

static <T> T createObjectFromDefaultConstructor(Class<T> aClass) throws ObjectFactoryException {
    Constructor<T> constructor = ConstructorUtils.getAccessibleConstructor(aClass);
    if (constructor == null) {
        throw new ObjectFactoryException("Unable to find a public no-arg constructor for <" + aClass + ">");
    }/*from  ww w.j a  v a2s.  co  m*/

    try {
        return constructor.newInstance();
    } catch (InstantiationException | IllegalAccessException | InvocationTargetException e) {
        throw new ObjectFactoryException(
                "Exception encountered while trying to create an instance of <" + aClass + ">", e);
    }
}

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From source file:com.offbynull.coroutines.instrumenter.asm.SimpleClassWriterTest.java

@Test
public void testCustomGetCommonSuperClassImplementation() throws Exception {
    // augment method to take in a single int argument
    methodNode.desc = Type.getMethodDescriptor(Type.VOID_TYPE, Type.INT_TYPE);

    // augment method instructions
    VariableTable varTable = new VariableTable(classNode, methodNode);

    Class<?> iterableClass = Iterable.class;
    Constructor arrayListConstructor = ConstructorUtils.getAccessibleConstructor(ArrayList.class);
    Constructor linkedListConstructor = ConstructorUtils.getAccessibleConstructor(LinkedList.class);
    Constructor hashSetConstructor = ConstructorUtils.getAccessibleConstructor(HashSet.class);
    Method iteratorMethod = MethodUtils.getAccessibleMethod(iterableClass, "iterator");

    Type iterableType = Type.getType(iterableClass);

    Variable testArg = varTable.getArgument(1);
    Variable listVar = varTable.acquireExtra(iterableType);

    /**/*from  w w  w .  ja va 2s . c  o  m*/
     * Collection it;
     * switch(arg1) {
     *     case 0:
     *         it = new ArrayList()
     *         break;
     *     case 1:
     *         it = new LinkedList()
     *         break;
     *     case 2:
     *         it = new HashSet()
     *         break;
     *     default: throw new RuntimeException("must be 0 or 1");
     * }
     * list.iterator();
     */
    LabelNode invokePoint = new LabelNode();
    InsnList methodInsnList = merge(
            tableSwitch(loadVar(testArg), throwException("must be 0 or 1"), 0,
                    merge(construct(arrayListConstructor), saveVar(listVar), jumpTo(invokePoint)),
                    merge(construct(linkedListConstructor), saveVar(listVar), jumpTo(invokePoint)),
                    merge(construct(hashSetConstructor), saveVar(listVar), jumpTo(invokePoint))),
            addLabel(invokePoint), call(iteratorMethod, InstructionUtils.loadVar(listVar)), pop(), // discard results of call
            returnDummy(Type.VOID_TYPE));

    methodNode.instructions = methodInsnList;

    // attemp to write out class -- since we're branching like this it should call getCommonSuperClass() with the types specified in
    // each of the switch cases. getCommonsuperClass() is the logic we explictly override and are testing. createJarAndLoad uses
    // simpleclasswriter
    try (URLClassLoader cl = createJarAndLoad(classNode)) {
        Object obj = cl.loadClass("SimpleStub").newInstance();

        // there should not be any verifer errors here
        MethodUtils.invokeMethod(obj, "fillMeIn", 0);
        MethodUtils.invokeMethod(obj, "fillMeIn", 1);
        MethodUtils.invokeMethod(obj, "fillMeIn", 2);
    }
}

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From source file:com.carmanconsulting.cassidy.util.CassidyUtils.java

public static boolean isInstantiable(Class<?> type) {
    return ConstructorUtils.getAccessibleConstructor(type) != null;
}

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From source file:therian.operator.convert.CopyingConverter.java

private static <T> Constructor<T> requireDefaultConstructor(Class<T> type) {
    return Validate.notNull(ConstructorUtils.getAccessibleConstructor(type),
            "Could not find default constructor for %s", type);
}

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