使用Java 8构造时Bean创建的ArrayOutOfBoundsException

Question

I am getting an ArrayIndexOutOfBoundsException on service start up (Bean creation) when i use Java 8 features.

Java 8 has been set up and has been working. The code compiles correctly. On service start, the service fails to listen to port as the beans don't get created. When i change the code (remove java 8 constructs) the service starts and everything works fine.

This is the code i am using (the working code for which the service starts):

for (Item itemObject : response) {
    if (itemObject.hasId()) {
        idList.add(String.valueOf(itemObject.Id());
    }
}

Same code using Java 8 constructs:

response.parallelStream()
        .filter(itemObject -> itemObject.hasId())
        .map(itemObject -> itemObject.getId())
        .forEach(id -> idList.add(id));

The bean for the class containing this piece of code is created using component scan.

The following is the exception message when the second code block is used in place of the first one:

Exiting with throwable: java.lang.IllegalArgumentException: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: URL [jar:file:/workspace/.../GetContainerIdForFcSkuAdapter.class]; nested exception is java.lang.ArrayIndexOutOfBoundsException: 51880
 java.lang.IllegalArgumentException: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: URL [jar:file:/workspace....Some.class]; nested exception is java.lang.ArrayIndexOutOfBoundsException: 51880

What does not make sense to me is, why is the code inside a function (which is not the constructor of the bean class) being covered while creating the bean. I ask this, because the exception is not there when i use the normal for loop instead of the parallel stream. Shouldn't an ArrayOutOfBoundsException arise when the function is called and this code is actually used.

How do i fix this?

Answer 1

Which version of Spring do you use? You need upgrade to Spring 4 to use Java 8 lambda expressions.

Answer 2

I found a bug recently when using Spring 3.0.5, which appears to be fixed in 4.0.5. Here are the details.

If you have a class that has a parameterized constructor and also has a method that uses a lambda expression (introduced in Java 8), then a ArrayIndexOutOfException occurs when creating a bean for that class.