singleton-enforcer

Enforce singletons really are singletons!

License	The Apache License, Version 2.0
GroupId	io.github.theangrydev
ArtifactId	singleton-enforcer
Last Version	2.1.0
Release Date	Oct 8, 2016
Type	jar
Description	singleton-enforcer Enforce singletons really are singletons!
Project URL	https://github.com/theangrydev/singleton-enforcer
Source Code Management	https://github.com/theangrydev/singleton-enforcer.git

Download singleton-enforcer

Filename	Size
singleton-enforcer-2.1.0.pom
singleton-enforcer-2.1.0.jar	10 KB
singleton-enforcer-2.1.0-sources.jar	3 KB
singleton-enforcer-2.1.0-javadoc.jar	28 KB

How to add to project

Apache Maven

<!-- https://jarcasting.com/artifacts/io.github.theangrydev/singleton-enforcer/ -->
<dependency>
    <groupId>io.github.theangrydev</groupId>
    <artifactId>singleton-enforcer</artifactId>
    <version>2.1.0</version>
</dependency>

Gradle Groovy

// https://jarcasting.com/artifacts/io.github.theangrydev/singleton-enforcer/
implementation 'io.github.theangrydev:singleton-enforcer:2.1.0'

Gradle Kotlin

// https://jarcasting.com/artifacts/io.github.theangrydev/singleton-enforcer/
implementation ("io.github.theangrydev:singleton-enforcer:2.1.0")

Apache Buildr

'io.github.theangrydev:singleton-enforcer:jar:2.1.0'

Apache Ivy

<dependency org="io.github.theangrydev" name="singleton-enforcer" rev="2.1.0">
  <artifact name="singleton-enforcer" type="jar" />
</dependency>

Groovy Grape

@Grapes(
@Grab(group='io.github.theangrydev', module='singleton-enforcer', version='2.1.0')
)

Scala SBT

libraryDependencies += "io.github.theangrydev" % "singleton-enforcer" % "2.1.0"

Leiningen

[io.github.theangrydev/singleton-enforcer "2.1.0"]

Dependencies

compile (3)

Group / Artifact	Type	Version
junit : junit	jar	4.12
net.bytebuddy : byte-buddy	jar	1.4.8
net.bytebuddy : byte-buddy-agent	jar	1.4.8

test (1)

Group / Artifact	Type	Version
org.assertj : assertj-core	jar	3.3.0

Project Modules

There are no modules declared in this project.

singleton-enforcer

Tool to enforce that certain classes are ony ever constructed once

Example:

public class ExampleTest {

    @Rule
    public SingletonEnforcer singletonEnforcer = SingletonEnforcer.enforcePackage("example");

    @Test(expected = AssertionError.class)
    public void singletonConstructedTwiceWillThrowException() {
        singletonEnforcer.during(() -> {
            new Singleton();
            new Singleton();
        }).checkSingletonsAreConstructedOnce(Singleton.class);
    }

    @Test(expected = AssertionError.class)
    public void leakedDependencyWillThrowAssertionError() {
        singletonEnforcer.during(() -> {
            LeakedDependencyInterface leakedDependency = new LeakedDependency();
            new SingletonWithDependency(leakedDependency, new Object());
            new ClassWithLeakedDependency(leakedDependency);
        }).checkDependencyIsNotLeaked(SingletonWithDependency.class, LeakedDependencyInterface.class);
    }
}

Dependency:

<dependency>
    <groupId>io.github.theangrydev</groupId>
    <artifactId>singleton-enforcer</artifactId>
    <version>2.1.0</version>
</dependency>

Releases

2.1.0

• Made the public API thread safe
• Added documentation for the public API

2.0.1

• Turned SingletonEnforcer into a JUnit @Rule
• Added a method SingletonEnforcer.during that takes a Runnable that should execute some code that the assertions will be made about
• Added a checks to make sure that the classes in the package to enforce are instrumented before use
• Added a check to make sure that instrumented classes are not used outside of SingletonEnforcer.during

1.0.1

• Tool to enforce that certain classes are ony ever constructed once
• SingletonEnforcer must be setUp before use with the package to cover and tearDown must be called after use
• SingletonEnforcer.checkSingletons checks that the given classes were only constructed once
• SingletonEnforcer.checkSingletonDependenciesAreNotLeaked checks that a dependency of a singleton is only used inside that singleton and not passed on to other objects

Versions

Version
2.1.0 Oct 8, 2016
2.0.1 Oct 8, 2016
2.0.0 Oct 8, 2016
1.0.1 Oct 7, 2016
1.0.0 Aug 1, 2016