docs: javadoc, readme

Author: csviri

README.md

@@ -3,10 +3,42 @@
 Jenvtest is similar to envtest, to support unit testing with API Server - just for Java:
 https://book.kubebuilder.io/reference/envtest.html
 
+It runs the API Server binaries directly (without nodes and other components). Thus, only etcd and Kubernetes API Server.
+
 Project is in early phases, heading towards mvp release.
 
 ## Usage 
 
+### Unit Tests
+
+See sample unit test [here](https://github.com/csviri/jenvtest/blob/e22ecef78b916f43e35832e1154da90361db2802/src/test/java/com/csviri/kubeapi/JUnitExtensionTest.java)
+
+```java
+@EnableAPIServer
+class JUnitExtensionTest {
+
+    @Test
+    void testCommunication() {
+        var client = new KubernetesClientBuilder().build();
+        client.resource(configMap()).createOrReplace();
+        var cm = client.resource(configMap()).get();
+
+        assertThat(cm).isNotNull();
+    }
+
+    private ConfigMap configMap() {
+        return new ConfigMapBuilder()
+                .withMetadata(new ObjectMetaBuilder()
+                        .withName("test1")
+                        .withNamespace("default")
+                        .build())
+                .withData(Map.of("key","data"))
+                .build();
+    }
+
+}
+```
+
 ### Download binaries
 
 [`setup-envtest`](https://pkg.go.dev/sigs.k8s.io/controller-runtime/tools/setup-envtest#section-readme) can be used

src/main/java/com/csviri/kubeapi/APIServerConfig.java

@@ -6,15 +6,18 @@ public class APIServerConfig {
 
     public static final String DIRECTORY_NAME = ".jenvtest";
 
+    /**
+     * Set home directory of the project. Default is ~/.jenvtest
+     **/
     private String jenvtestDir;
-    // todo support wildcard 1.26.*
+
     /**
      * Sample: 1.26.1, 1.25.0
      */
     private String apiServerVersion;
 
     public APIServerConfig() {
-        this.jenvtestDir = System.getProperty("user.home") + File.separator + DIRECTORY_NAME;
+        this.jenvtestDir = new File(System.getProperty("user.home"), DIRECTORY_NAME).getPath();
     }
 
     public String getJenvtestDirectory() {
@@ -36,6 +39,6 @@ public APIServerConfig setApiServerVersion(String apiServerVersion) {
     }
 
     public String logDirectory() {
-        return new File(jenvtestDir,"logs").getPath();
+        return new File(jenvtestDir, "logs").getPath();
     }
 }