mariofusco

1. “null is used in java to represent uninitialized fields”

I thought this is what constructors are for, isn’t it? 
So either you can initialize a field in the constructor or it has a meaning in your domain to 
leave that field empty and in this 2nd case it should be represented with an Optional.

2. “It is not possible to write a method that takes either an X or an Optional”

These methods clearly have 2 different semantics and then it is correct that they are 2 
totally separated method. In the first case you pass a value of type X that for sure is 

mariofusco

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>org.drools</groupId>
    <artifactId>droolsjbpm-integration</artifactId>
    <version>6.3.0-SNAPSHOT</version>

mariofusco

package mf.java8ws.examples.example15;

import java.util.List;
import java.util.Random;
import java.util.function.Function;
import java.util.stream.IntStream;

import static java.util.stream.Collectors.toList;

public class Main {

mariofusco

package org.drools.compiler.integrationtests;

import org.junit.Test;
import org.kie.api.io.ResourceType;
import org.kie.api.runtime.KieSession;
import org.kie.internal.utils.KieHelper;

import java.util.List;

public class NpeOnQueryTest {

mariofusco

/**
 * 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
 *

mariofusco

/**
 * 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
 *

mariofusco

/*
 * Copyright 2005 JBoss Inc
 *
 * Licensed 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

mariofusco

import java.util.function.Predicate;

public class TypeInference {

    public static void main( String[] args ) {
        // compile
        Pattern<String> p1 = pattern(String.class, expr(s -> s.length() > 3, id("expr1")));
        
        // don't compile
        Pattern<String> p2 = pattern(String.class, expr(s -> s.length() > 3).id("expr1"));

mariofusco

"ForkJoinPool.commonPool-worker-1@10167" daemon prio=5 tid=0x21 nid=NA waiting for monitor entry
  java.lang.Thread.State: BLOCKED
	 blocks ForkJoinPool.commonPool-worker-3@10169
	 waiting for ForkJoinPool.commonPool-worker-3@10169 to release lock on <0x2880> (a org.drools.core.common.ProjectClassLoader$DefaultInternalTypesClassLoader)
	  at java.lang.ClassLoader.checkCerts(ClassLoader.java:887)
	  at java.lang.ClassLoader.preDefineClass(ClassLoader.java:668)
	  at java.lang.ClassLoader.defineClass(ClassLoader.java:761)
	  at java.lang.ClassLoader.defineClass(ClassLoader.java:642)
	  at org.drools.core.common.ProjectClassLoader$DefaultInternalTypesClassLoader.defineClass(ProjectClassLoader.java:424)
	  at org.drools.core.common.ProjectClassLoader.defineType(ProjectClassLoader.java:209)

mariofusco

Exception in thread "main" java.lang.RuntimeException: Unable to get KieModule, Errors Existed: Error Messages:
Message [id=1, level=ERROR, path=src/main/java/com/wellsfargo/rules/RS7488_2_27__RF6366_339_50359134/Rules00e9ba29706046e390d6585be51d81f0RuleMethods1.java, line=49, column=1
   text=code too large]
Message [id=2, level=ERROR, path=src/main/java/com/wellsfargo/rules/RS7488_2_27__RF6366_339_50359134/Rules00e9ba29706046e390d6585be51d81f0RuleMethods1.java, line=0, column=0
   text=Java source of src/main/java/com/wellsfargo/rules/RS7488_2_27__RF6366_339_50359134/Rules00e9ba29706046e390d6585be51d81f0RuleMethods1.java in error:
package com.wellsfargo.rules.RS7488_2_27__RF6366_339_50359134;

import java.util.*;
import org.drools.model.*;
import org.drools.modelcompiler.dsl.pattern.D;