ljnelson

// I have been programming Java since 1996 at both the application and systems level.
// This seemingly elementary problem that I would fail on any junior-level interview
// gave me absolute fits.  I wanted to capture it here for the benefit of other
// dullards like me.   You are not alone.
//
// Suppose you have some number of arrays (let's say 2).  Like so:
//
//   final Object[] o0 = new Object[] { String.class, Number.class };
//   final Object[] o1 = new Object[] { Object.class };
//

ljnelson

import net.bytebuddy.description.modifier.Visibility;

import net.bytebuddy.dynamic.DynamicType;

import net.bytebuddy.implementation.FieldAccessor;
import net.bytebuddy.implementation.MethodCall;

import static net.bytebuddy.implementation.MethodCall.invoke;

import static net.bytebuddy.matcher.ElementMatchers.named;

ljnelson

.level=INFO
handlers=io.helidon.common.HelidonConsoleHandler
java.util.logging.SimpleFormatter.format=%1$tY.%1$tm.%1$td %1$tH:%1$tM:%1$tS %4$s %3$s !thread!: %5$s%6$s%n

com.zaxxer.hikari.level=INFO
h2database.level=WARNING
io.netty.level=INFO
org.eclipse.persistence.level=FINE
org.glassfish.jersey.server.level=CONFIG

ljnelson

@GET
@Path("response/{salutation}")
@Produces("text/plain")
@Transactional 
public String getResponse(@PathParam("salutation") String salutation) {
    final Greeting greeting = this.em.find(Greeting.class, salutation);
    final String returnValue;
    if (greeting == null) {
        returnValue = null;
    } else {

ljnelson

@PersistenceContext 
private EntityManager em;

ljnelson

@Dependent 
public class ExampleResource {
    // rest of class follows
}

ljnelson

import javax.enterprise.context.Dependent;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.transaction.Transactional;
import javax.ws.rs.PathParam;

ljnelson

<plugin>
    <groupId>com.ethlo.persistence.tools</groupId>
    <artifactId>eclipselink-maven-plugin</artifactId>
    <version>2.7.1.1</version>
    <dependencies> 
        <dependency>
            <groupId>javax.annotation</groupId>
            <artifactId>javax.annotation-api</artifactId>
            <version>1.3.1</version>
        </dependency>

ljnelson

package io.helidon.example.jpa;

import java.io.Serializable;
import java.util.Objects;

import javax.persistence.Access;
import javax.persistence.AccessType;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;

ljnelson

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.2" 
             xmlns="http://xmlns.jcp.org/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
                                 http://xmlns.jcp.org/xml/ns/persistence/persistence_2_2.xsd">
    <persistence-unit name="greeting" transaction-type="JTA"> 
        <description>A persistence unit for the greeting example.</description>
        <jta-data-source>greetingDataSource</jta-data-source> 
        <class>io.helidon.example.jpa.Greeting</class>