Add minimal documentation for the Java SDK (#1592)

Author: giograno

content/en/user-guide/tools/localstack-sdk/java/index.md

@@ -0,0 +1,77 @@
+---
+title: "Java"
+weight: 1
+description: Use the LocalStack SDK for Java
+---
+
+## Introduction
+
+You can use the LocalStack SDK for Java to develop Java applications that interact with the LocalStack platform and internal developer endpoints.
+The SDK extends the REST API, offering an object-oriented interface for easier use.
+
+The LocalStack SDK for Java currently supports these features:
+
+- Save, list, load, and delete Cloud Pods.
+- Manage fault configurations for the Chaos API.
+
+{{< callout >}}
+This SDK is still in a preview phase, and will be subject to fast and breaking changes.
+{{< /callout >}}
+
+## Installation
+
+The best way to use the LocalStack SDK for Java in your project is to consume it from Maven Central.
+You can use Maven to import the entire SDK into your project.
+
+```xml
+<dependency>
+    <groupId>cloud.localstack</groupId>
+    <artifactId>localstack-sdk</artifactId>
+    <version>0.0.1</version>
+</dependency>
+```
+
+Similarly, you can copy the following line in the dependencies block of your `build.gradle(.kts)` file, if you are using Gradle as a build tool.
+
+```kotlin
+implementation("cloud.localstack:localstack-sdk:0.0.1")
+```
+
+## Quick Start
+
+Currently, the LocalStack SDK for Java only supports Chaos and Cloud Pods APIs.
+Both these features have a client that can be instantiated from the `cloud.localstack.sdk.chaos` and
+`cloud.localstack.sdk.pods` package, respectively.
+
+The clients accept requests built by using the [builder pattern](https://en.wikipedia.org/wiki/Builder_pattern).
+For instance, let us imagine the case in which you want to add a fault rule for S3 on the `us-east-1` region.
+You first need to use the `FaultRuleRequest` class to build a fault rule request.
+Then, you need to pass such a request object to the `addFaultRules` method of a created `ChaosClient`.
+
+```java
+import cloud.localstack.sdk.chaos.ChaosClient;
+import cloud.localstack.sdk.chaos.requests.FaultRuleRequest;
+
+var client = new ChaosClient();
+var faultRuleRequest = new FaultRuleRequest.Builder().faultRule("s3", "us-east-1").build();
+var addedRules = client.addFaultRules(request);
+```
+
+As a second example, let us look at the necessary code to save and load a Cloud Pod.
+Similarly to the `ChaosClient`, the `PodsClient` exposes two functions, `savePod` and `loadPod`, which expect a `SavePodRequest` and a `LoadPodRequest`, respectively.
+The resulting code is the following:
+
+```java
+import cloud.localstack.sdk.pods.PodsClient;
+import cloud.localstack.sdk.pods.requests.LoadPodRequest;
+import cloud.localstack.sdk.pods.requests.SavePodRequest;
+
+var podsClient = new PodsClient();
+// save a cloud pod
+var saveRequest = new SavePodRequest.Builder().podName(POD_NAME).build();
+podsClient.savePod(saveRequest);
+
+//load a cloud pod
+var loadRequest = new LoadPodRequest.Builder().podName(POD_NAME).build();
+podsClient.loadPod(loadRequest);
+```