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How to setup java for dynamo db for first time?

I am new to use Dynamo DB,
I want to know how to setup pom.xml like if I use maven what is dependency use for dynamodb
<dependencies>
<dependency>
<groupId>??</groupId>
<artifactId>??</artifactId>
<version>??</version>
<scope>test</scope>
</dependency>
<dependency>
or any example source code which I can research how to use it?
For dynamodb and how to setup like list of table and create column one by one in dynamodb any source can i read ?

if you want to use aws dynamo DB so you can use following code:
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-java-sdk-dynamodb</artifactId>
<version>1.11.784</version>
</dependency>
you can use following example for setup by using below link
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/CodeSamples.Java.html

Dependency in pom is:
<dependency>
<groupId>com.github.derjust</groupId>
<artifactId>spring-data-dynamodb</artifactId>
<version>5.1.0</version>
</dependency>
Next if You want to use it in code You need to read about #DynamoDBTable .
Best lecture about it have of course Baeldung

Twitter4j: Cannot use StatusListener cannot be resolved

I'm struggling with Twitter4j. I am using a Maven project with the following Twitter4j dependency:
<dependency>
<groupId>org.twitter4j</groupId>
<artifactId>twitter4j-core</artifactId>
<version>[4.0,)</version>
</dependency>
However every time I try and declare a StatusListener, I get Cannot resolve symbol 'StatusListener' even though I'm importing import twitter4j.*;.
Anyone know why this might happen when I can use pretty much all other features of Twitter4j?

I needed to add
<dependency>
<groupId>org.twitter4j</groupId>
<artifactId>twitter4j-stream</artifactId>
<version>[4.0,)</version>
</dependency>
As a dependency to my pom.xml. Turns out the Streaming API and all related classes are in a different part of the Twitter4J ecosystem.

As twitter4j lib contains the core, async, example, and a stream part. You should try to include all these but mainly the stream dependency contains the status listener method. I hope it solves your problem.

How to inject dependecies using Governator within TestNG test cases?

I'm working on a test automation framework which use TestNG. I decided to use Dependency Injection pattern in order to implement more readable, reusable page objects and tests.
I've chosen Google Guice due to TestNG provides built-in support to inject test objects with Guice Modules. I only had to specify my Guice Modules as you can see at next code snippet:
#Guice(modules = CommModule.class)
public class CommunicationTest {
#Inject
private Communication comms;
#Test
public void testSendMessage() {
Assertions.assertThat(comms.sendMessage("Hello World!")).isTrue();
}
}
So far so good, although I'm going to need more advance DI features such as:
Lifecycle management
Configuration to field mapping
Generic binding annotations
Therefore, I'd like to use Netflix/Governator since it enhance Google Guice with these features. In order to trigger Governator features I must create the Injector through it instead of TestNG. e.g:
Injector injector = LifecycleInjector.builder()
.withModules(CommModules.class).build().createInjector();
And I'd like to do it mostly transparent as possible like TestNG does it.
I would like to know if:
Is it possible to provide my own Injector instance to TestNG in order to reuse #Guice annotation approach ?
Do you know any library for integrating Governator with TestNG ?
You can find in here what I've done so far.

This was not possible until now. I have fixed this in the latest snapshot version of TestNG. It should be available in the upcoming version of TestNG (Any version greater than 7.0.0)
The issue that I created to track this : https://github.com/cbeust/testng/issues/2199
In a nutshell, you can do the following :
Implement the interface org.testng.IInjectorFactory
Plugin the fully qualified class name of the newly created implementation via the command line argument -dependencyinjectorfactory

Since Allow user to provide DI Injector TestNG feature is going to be present in versions greater than 7.0.0. I implemented a solution using TestNG version 7.0.0 listeners.
Firstly, I created a module called autopilot-testng-runner with the following dependencies:
<dependencies>
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
</dependency>
<dependency>
<groupId>com.google.inject</groupId>
<artifactId>guice</artifactId>
</dependency>
<dependency>
<groupId>com.netflix.governator</groupId>
<artifactId>governator</artifactId>
</dependency>
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>javax.annotation-api</artifactId>
</dependency>
<dependency>
<groupId>org.javassist</groupId>
<artifactId>javassist</artifactId>
</dependency>
</dependencies>
This module contains the artifacts described at next:
#AutopilotTest: Custom annotation for declaring which Guice modules must be used for creating the Injector with LifecycleInjector.builder(). I couldn't reuse #Guice annotation due to TestNG also will create its Injector and declared dependencies will be created twice.
AutopilotSuiteListener: Implementation of ISuiteListener for creating the parent Injector, Governator's LifecycleManager instance and bind configuration properties before Suite starts. Therefore each Suite is going to have a parent Injector built with Governator and a life-cycle manager.
AutopilotTestListener: ITestListener implementation in charge of injecting dependencies in the running test case.
META-INF/services/org.testng.ITestNGListener: Service provider configuration file containing the fully qualified names of both ITestNGListener implementations.
Then, I added autopilot-testng-runner as a maven dependency in my project
<dependency>
<groupId>com.github.eljaiek.playground</groupId>
<artifactId>autopilot-testng-runner</artifactId>
<version>${project.version}</version>
<scope>test</scope>
</dependency>
And finally, I replaced #Guice annotation with #AutopilotTest
#AutopilotTest(modules = CommModule.class)
public class CommunicationTest {
#Inject
private Communication comms;
#Test
public void testSendMessage() {
Assertions.assertThat(comms.sendMessage("Hello World!")).isTrue();
}
}

How to execute mybatis-spring-boot-starter-test?

For mybatis-spring-boot-starter-test I see no main method and even no Java file. It has two dependencies of which mybatis-spring-boot-test-autoconfigure contains some test files and I can execute them while spring-boot-starter-test just has a pom file.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-test-autoconfigure</artifactId>
</dependency>
So how can I execute these test modules? It I can't, it's created for what?

This module is not for "execution". Take a look at their docs:
What is MyBatis-Spring-Boot-Starter-Test?
The MyBatis-Spring-Boot-Starter-Test help creating a test cases for MyBatis component using the MyBatis-Spring-Boot-Starter.
By using this module you will can be:
Can use the #MybatisTest that setup test components for testing pure MyBatis component
Can import dependency artifacts for performing tests for pure MyBatis component
So, this module provides you #MybatisTest from mybatis-spring-boot-test-autoconfigure. That's, basically, what "starters" are: a group of (possibly one, like in this case) dependencies that are intended to work together to provide some features.
Read more about using #MybatisTest.

Why is Maven not resolving all dependencies for commons-configuration?

Summary
When trying XMLConfiguration configuration = new XMLConfiguration("config/config.xml"); with only commons-configuration 1.10 I need to add more depencies (namely commons-collections not newer than 3.2.1) to my maven setup. Why is that so and why doesn't maven simply resolve all needed dependencies?
Details
I am trying to get commons-configuration to work. First I wanted to use the latest version, 2.0-alpha2, which didn't work well at all since I was unable to configure Maven to download the correct ressources - but that is another story.
After I found out that version 1.10 is in fact "one point ten" (not "one point one zero") and thus the latest version of commons-configuration 1 (and covered by the tutorials), I decided to give it a try instead.
For my maven dependencies (integrated in eclipse) I used:
<dependency>
<groupId>commons-configuration</groupId>
<artifactId>commons-configuration</artifactId>
<version>1.10</version>
</dependency>
However, when trying out this example:
package main;
import java.util.Iterator;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.XMLConfiguration;
public class ConfigurationTest {
public static void main(String... args) {
try {
XMLConfiguration configuration =
new XMLConfiguration("config/config.xml");
Iterator<String> iterator = configuration.getKeys();
while (iterator.hasNext()) {
System.out.println(iterator.next());
}
} catch (ConfigurationException e) {
e.printStackTrace();
}
}
}
with the following config.xml:
<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<configuration>
<property>value</property>
<nestedproperty>
<arrayvalue>0,1,2,3,4</arrayvalue>
<property>anothervalue</property>
</nestedproperty>
</configuration>
I got the error:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/collections/CollectionUtils
at org.apache.commons.configuration.XMLConfiguration.constructHierarchy(XMLConfiguration.java:640)
at org.apache.commons.configuration.XMLConfiguration.initProperties(XMLConfiguration.java:596)
at org.apache.commons.configuration.XMLConfiguration.load(XMLConfiguration.java:1009)
at org.apache.commons.configuration.XMLConfiguration.load(XMLConfiguration.java:972)
at org.apache.commons.configuration.XMLConfiguration$XMLFileConfigurationDelegate.load(XMLConfiguration.java:1647)
at org.apache.commons.configuration.AbstractFileConfiguration.load(AbstractFileConfiguration.java:324)
at org.apache.commons.configuration.AbstractFileConfiguration.load(AbstractFileConfiguration.java:261)
at org.apache.commons.configuration.AbstractFileConfiguration.load(AbstractFileConfiguration.java:238)
at org.apache.commons.configuration.AbstractHierarchicalFileConfiguration.load(AbstractHierarchicalFileConfiguration.java:184)
at org.apache.commons.configuration.AbstractHierarchicalFileConfiguration.<init>(AbstractHierarchicalFileConfiguration.java:95)
at org.apache.commons.configuration.XMLConfiguration.<init>(XMLConfiguration.java:261)
at main.ConfigurationTest.main(ConfigurationTest.java:12)
I first hoped they (not me, of course) just screwed up some maven dependencies and since I wouldn't bother which version to use anyway anymore (I didn't get 2.0 to work, remember?) I decided to go down to version 1.9 by replacing the maven dependency with:
<dependency>
<groupId>commons-configuration</groupId>
<artifactId>commons-configuration</artifactId>
<version>1.9</version>
</dependency>
That solved the problem pretty well, the test case is running:
property
nestedproperty.arrayvalue
nestedproperty.property
But when I tried to implement a similar example to the one referenced in Very simple Apache-commons configuration example throws NoClassDefFoundError and its follow-up question I got the exact same error which is referenced there - but the solution, importing org.apache.commons.beanutils.PropertyUtils is not working as I am missing the beanutils. So basically by downgrading I just switched from the error of missing the collections to missing beanutils.
There is a dependency overview where you can see which dependencies are used when you do what. I was a bit suprised to learn that version 1.10 now used other dependencies (namely the CollectionUtils) than 1.9 did in the constructor call. Since there were dependency problems in 1.10 as well as in 1.9 I just sticked to the newer version.
I found the CollectionUtils located in the following artifact (as I was pointed there by its maven repository):
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-collections4</artifactId>
<version>4.0</version>
</dependency>
Sadly that one (not obvious to me at first) doesn't define the class CollectionUtils in the package collections, but in the package collections4. It was hinted at this problem on the dependency overview, but they only mentioned possible problems with earlier versions... I appeared to be at a point of not thinking much about it anymore but simply changed the dependency to:
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
</dependency>
I got everything to work (more or less, but the Exceptions I get now are not anymore depending on missing class definitions) after using these dependencies:
<dependencies>
<dependency>
<groupId>commons-configuration</groupId>
<artifactId>commons-configuration</artifactId>
<version>1.10</version>
</dependency>
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
</dependency>
<dependency>
<groupId>commons-beanutils</groupId>
<artifactId>commons-beanutils</artifactId>
<version>1.9.2</version>
</dependency>
</dependencies>
Why do I have to add the dependencies myself? I thought the whole point in using maven is to avoid having to do such things and in terms of javadocs and source files it does a pretty good job.
By now I am convinced that the dependencies are not included in the hierarchy by design (is that so?), probably to avoid overhead. However is there a way to either simply get all dependencies at once or even better to get all dependencies I need? And why is it designed this way?

If we analyse commons-configuration's POM we see that the commons-collections dependency is optional:
<dependencies>
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
<optional>true</optional>
</dependency>
...
Furthermore, from the Maven docs:
If a user wants to use functionality related to an optional
dependency, they will have to redeclare that optional dependency in
their own project.

This issue is explained on the Runtime dependencies page of the Commons Configuration website.
Quoting from that page:
A lot of dependencies are declared in the Maven POM. These are all needed during compile time. On runtime however you only need to add the dependencies to your classpath that are required by the parts of the Commons Configuration package you are using. The following table helps you to determine which dependencies you have to include based on the components you intend to use.
The other answers explain why this works from a Maven perspective. This answer is intended to provide a defence, of sorts, to the Commons Configuration folks. They did at least warn you!
In cases where the dependencies are on other Apache Commons components, they've taken the time to test with a variety of versions and have posted information on compatibility at the bottom of that page.

Maven tries to resolve all necessary dependencies for a library you're using in your pom. Well sometimes you have some dependencies which are only necessary for some specific features and you don't want to force the user of your dependency to download it if he doesn't use it. Then you're declaring your dependency as optional. This happened with commons-collections within commons-configuration. See commons-configuration-pom here