neo4j：简单的示例抛出java.lang.NoClassDefFoundError：scala / Function0

Question

I try to build up a very simple neo4j db for practicing:

public static void main(String[] args) {
    Map<String, String> config = new HashMap<String, String>();
    config.put( "neostore.nodestore.db.mapped_memory", "10M" );
    config.put( "string_block_size", "60" );
    config.put( "array_block_size", "300" );
    GraphDatabaseService graphDb = new GraphDatabaseFactory()
        .newEmbeddedDatabaseBuilder( "db" )
        .setConfig( config )
        .newGraphDatabase();

    ExecutionEngine engine = new ExecutionEngine(graphDb, StringLogger.DEV_NULL);
}

I get the following exception while executing it: Exception in thread "main" java.lang.NoClassDefFoundError: scala/Function0

Do you have any idea how to get it working?

Answer 1

Questions about this error is listed among the common Java questions on the 'java' tag wiki , and for a general answer you can begin by reading about it here . To know why the class definition cannot be found in your specific case it would be helpful first to know exactly what definition it is that cannot be found, so please edit your question to include the full stack trace. Maybe someone else will recognize your exact error, all I can see from that one line is that the JVM is unable to load some Scala definition, and that probably you need to include some missing dependency or clean up conflicting versions in your dependency tree.

Answer 2

我们的解决方案是在我们的IDE中添加scala支持。