feat: send feature flag event to product analytics (3/4)

posthog/src/main/java/com/posthog/java/Getter.java

@@ -0,0 +1,21 @@
+package com.posthog.java;
+
+import org.json.JSONObject;
+
+import java.util.Map;
+
+/*
+ * Getter interface for making HTTP GET requests to the PostHog API
+ */
+interface Getter {
+
+    /*
+     * Make a GET request to the PostHog API
+     *
+     * @param route The route to make the GET request to
+     * @param headers The headers to include in the GET request
+     * @return The JSON response from the GET request
+     */
+    JSONObject get(String route, Map<String, String> headers);
+
+}

posthog/src/main/java/com/posthog/java/HttpSender.java → posthog/src/main/java/com/posthog/java/HttpInteractor.java

@@ -3,6 +3,7 @@
 import java.io.IOException;
 import java.time.Duration;
 import java.util.List;
+import java.util.Map;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -14,7 +15,7 @@
 import okhttp3.RequestBody;
 import okhttp3.Response;
 
-public class HttpSender implements Sender {
+public class HttpInteractor implements Sender, Getter {
     private String apiKey;
     private String host;
     private OkHttpClient client;
@@ -53,12 +54,12 @@ public Builder initialRetryInterval(Duration initialRetryInterval) {
             return this;
         }
 
-        public HttpSender build() {
-            return new HttpSender(this);
+        public HttpInteractor build() {
+            return new HttpInteractor(this);
         }
     }
 
-    private HttpSender(Builder builder) {
+    private HttpInteractor(Builder builder) {
         this.apiKey = builder.apiKey;
         this.host = builder.host;
         this.maxRetries = builder.maxRetries;
@@ -188,4 +189,35 @@ public JSONObject post(String route, String distinctId) {
         }
         return null;
     }
+
+    @Override
+    public JSONObject get(String route, Map<String, String> headers) {
+        final String url = this.host + route;
+        final Request.Builder requestBuilder = new Request.Builder()
+                .url(url);
+
+        if (headers != null) {
+            headers.forEach(requestBuilder::addHeader);
+        }
+
+        final Request request = requestBuilder.build();
+
+        try (final Response response = this.client.newCall(request).execute()) {
+            if (!response.isSuccessful()) {
+                System.err.println("Failed to fetch feature flags: " + response.message());
+                return null;
+            }
+
+            if (response.body() == null) {
+                System.err.println("Failed to fetch feature flags: response body is null");
+                return null;
+            }
+
+            return new JSONObject(response.body().string());
+        } catch (IOException e) {
+            System.err.println("Failed to fetch feature flags: " + e.getMessage());
+        }
+
+        return null;
+    }
 }

posthog/src/main/java/com/posthog/java/InconclusiveMatchException.java

@@ -0,0 +1,7 @@
+package com.posthog.java;
+
+public class InconclusiveMatchException extends Exception {
+    public InconclusiveMatchException(String message) {
+        super(message);
+    }
+}

posthog/src/main/java/com/posthog/java/LimitedSizeMap.java

@@ -0,0 +1,26 @@
+package com.posthog.java;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+class LimitedSizeMap<K, V> extends LinkedHashMap<K, V> {
+    private final int maxSize;
+
+    LimitedSizeMap(int maxSize) {
+        super(maxSize, 0.75f, false);
+        this.maxSize = maxSize;
+    }
+
+    @Override
+    public V put(K key, V value) {
+        if (size() >= this.maxSize) {
+            clear();
+        }
+        return super.put(key, value);
+    }
+
+    @Override
+    protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
+        return false; // We handle the removal logic in the put method
+    }
+}