diff --git a/lib/src/main/java/javasdk/ErrorCode.java b/lib/src/main/java/javasdk/ErrorCode.java
index da947d5e..2e3710b2 100644
--- a/lib/src/main/java/javasdk/ErrorCode.java
+++ b/lib/src/main/java/javasdk/ErrorCode.java
@@ -1,5 +1,5 @@
 package javasdk;
 
 public enum ErrorCode {
-    PROVIDER_NOT_READY, FLAG_NOT_FOUND, PARSE_ERROR, TYPE_MISMATCH, GENERAL;
+    PROVIDER_NOT_READY, FLAG_NOT_FOUND, PARSE_ERROR, TYPE_MISMATCH, GENERAL
 }
diff --git a/lib/src/main/java/javasdk/FlagValueType.java b/lib/src/main/java/javasdk/FlagValueType.java
index ce51c018..c3a060af 100644
--- a/lib/src/main/java/javasdk/FlagValueType.java
+++ b/lib/src/main/java/javasdk/FlagValueType.java
@@ -1,5 +1,5 @@
 package javasdk;
 
 public enum FlagValueType {
-    STRING, NUMBER, OBJECT, BOOLEAN;
+    STRING, NUMBER, OBJECT, BOOLEAN
 }
diff --git a/lib/src/main/java/javasdk/HookContext.java b/lib/src/main/java/javasdk/HookContext.java
index 6ce25bf5..66533ac7 100644
--- a/lib/src/main/java/javasdk/HookContext.java
+++ b/lib/src/main/java/javasdk/HookContext.java
@@ -7,7 +7,7 @@ public class HookContext<T> {
     EvaluationContext ctx;
     FeatureProvider provider;
     T defaultValue;
-    HookEvaluation executedHooks;
+    HookEvaluation<T> executedHooks;
 
     public static <T> HookContext<T> from(String key, FlagValueType type, Client client, EvaluationContext ctx, T defaultValue) {
         HookContext<T> hc = new HookContext<>();
@@ -15,7 +15,7 @@ public class HookContext<T> {
         hc.type = type;
         hc.client = client;
         hc.ctx = ctx;
-        hc.executedHooks = new HookEvaluation();
+        hc.executedHooks = new HookEvaluation<T>();
         hc.defaultValue = defaultValue;
         return hc;
     }
diff --git a/lib/src/main/java/javasdk/HookEvaluation.java b/lib/src/main/java/javasdk/HookEvaluation.java
index b15b5823..31e2379a 100644
--- a/lib/src/main/java/javasdk/HookEvaluation.java
+++ b/lib/src/main/java/javasdk/HookEvaluation.java
@@ -8,22 +8,22 @@ import java.util.Collections;
 import java.util.List;
 
 @Data
-public class HookEvaluation {
-    private List<Hook> before = new ArrayList<>();
-    private List<Hook> after = new ArrayList<>();
-    private List<Hook> error = new ArrayList<>();
-    private List<Hook> afterAll = new ArrayList<>();
+public class HookEvaluation<T> {
+    private List<Hook<T>> before = new ArrayList<>();
+    private List<Hook<T>> after = new ArrayList<>();
+    private List<Hook<T>> error = new ArrayList<>();
+    private List<Hook<T>> afterAll = new ArrayList<>();
 
-    public void addBefore(Hook h) {
+    public void addBefore(Hook<T> h) {
         before.add(h);
     }
-    public void addAfter(Hook h) {
+    public void addAfter(Hook<T> h) {
         after.add(h);
     }
-    public void addError(Hook h) {
+    public void addError(Hook<T> h) {
         error.add(h);
     }
-    public void addAfterAll(Hook h) {
+    public void addAfterAll(Hook<T> h) {
         afterAll.add(h);
     }
 }
diff --git a/lib/src/main/java/javasdk/NoOpProvider.java b/lib/src/main/java/javasdk/NoOpProvider.java
index 438948b1..d169b19b 100644
--- a/lib/src/main/java/javasdk/NoOpProvider.java
+++ b/lib/src/main/java/javasdk/NoOpProvider.java
@@ -4,7 +4,7 @@ import lombok.Getter;
 
 public class NoOpProvider<T extends EvaluationContext> implements FeatureProvider {
     @Getter
-    private String name = "No-op Provider";
+    private final String name = "No-op Provider";
 
     @Override
     public ProviderEvaluation<Boolean> getBooleanEvaluation(String key, Boolean defaultValue, EvaluationContext ctx, FlagEvaluationOptions options) {
diff --git a/lib/src/main/java/javasdk/OpenFeatureClient.java b/lib/src/main/java/javasdk/OpenFeatureClient.java
index 00324770..fa6fa7d0 100644
--- a/lib/src/main/java/javasdk/OpenFeatureClient.java
+++ b/lib/src/main/java/javasdk/OpenFeatureClient.java
@@ -11,9 +11,9 @@ import java.util.List;
 
 public class OpenFeatureClient implements Client {
     private final OpenFeatureAPI openfeatureApi;
-    @Getter private String name;
-    @Getter private String version;
-    @Getter private List<Hook> clientHooks;
+    @Getter private final String name;
+    @Getter private final String version;
+    @Getter private final List<Hook> clientHooks;
 
     public OpenFeatureClient(OpenFeatureAPI openFeatureAPI, String name, String version) {
         this.openfeatureApi = openFeatureAPI;
@@ -124,32 +124,32 @@ public class OpenFeatureClient implements Client {
 
     @Override
     public String getStringValue(String key, String defaultValue) {
-        return null;
+        return this.getStringDetails(key, defaultValue).getValue();
     }
 
     @Override
     public String getStringValue(String key, String defaultValue, EvaluationContext ctx) {
-        return null;
+        return this.getStringDetails(key, defaultValue, ctx).getValue();
     }
 
     @Override
     public String getStringValue(String key, String defaultValue, EvaluationContext ctx, FlagEvaluationOptions options) {
-        return null;
+        return this.getStringDetails(key, defaultValue, ctx, options).getValue();
     }
 
     @Override
     public FlagEvaluationDetails<String> getStringDetails(String key, String defaultValue) {
-        return null;
+        return this.evaluateFlag(FlagValueType.STRING, key, defaultValue, null, null);
     }
 
     @Override
     public FlagEvaluationDetails<String> getStringDetails(String key, String defaultValue, EvaluationContext ctx) {
-        return null;
+        return this.evaluateFlag(FlagValueType.STRING, key, defaultValue, ctx, null);
     }
 
     @Override
     public FlagEvaluationDetails<String> getStringDetails(String key, String defaultValue, EvaluationContext ctx, FlagEvaluationOptions options) {
-        return null;
+        return this.evaluateFlag(FlagValueType.STRING, key, defaultValue, ctx, options);
     }
 
     @Override
diff --git a/lib/src/main/java/javasdk/ProviderEvaluation.java b/lib/src/main/java/javasdk/ProviderEvaluation.java
index ff38cd0e..0b5a00dc 100644
--- a/lib/src/main/java/javasdk/ProviderEvaluation.java
+++ b/lib/src/main/java/javasdk/ProviderEvaluation.java
@@ -2,7 +2,6 @@ package javasdk;
 
 import lombok.Builder;
 import lombok.Data;
-import lombok.NoArgsConstructor;
 
 import javax.annotation.Nullable;
 
diff --git a/lib/src/main/java/javasdk/Reason.java b/lib/src/main/java/javasdk/Reason.java
index e7e5cfc3..b573a0d6 100644
--- a/lib/src/main/java/javasdk/Reason.java
+++ b/lib/src/main/java/javasdk/Reason.java
@@ -1,5 +1,5 @@
 package javasdk;
 
 public enum Reason {
-    DISABLED, SPLIT, TARGETING_MATCH, DEFAULT, UNKNOWN, ERROR;
+    DISABLED, SPLIT, TARGETING_MATCH, DEFAULT, UNKNOWN, ERROR
 }
diff --git a/lib/src/main/java/javasdk/exceptions/FlagNotFoundError.java b/lib/src/main/java/javasdk/exceptions/FlagNotFoundError.java
index 1c482443..2dcfd7cd 100644
--- a/lib/src/main/java/javasdk/exceptions/FlagNotFoundError.java
+++ b/lib/src/main/java/javasdk/exceptions/FlagNotFoundError.java
@@ -4,5 +4,5 @@ import javasdk.ErrorCode;
 import lombok.Getter;
 
 public class FlagNotFoundError extends OpenFeatureError {
-    @Getter private ErrorCode errorCode = ErrorCode.GENERAL;
+    @Getter private final ErrorCode errorCode = ErrorCode.GENERAL;
 }
diff --git a/lib/src/main/java/javasdk/exceptions/GeneralError.java b/lib/src/main/java/javasdk/exceptions/GeneralError.java
index 2ce23b46..45e84ef7 100644
--- a/lib/src/main/java/javasdk/exceptions/GeneralError.java
+++ b/lib/src/main/java/javasdk/exceptions/GeneralError.java
@@ -4,8 +4,8 @@ import javasdk.ErrorCode;
 import lombok.Getter;
 
 public class GeneralError extends OpenFeatureError{
-    @Getter private ErrorCode errorCode = ErrorCode.GENERAL;
-    private final String message;
+    @Getter private final ErrorCode errorCode = ErrorCode.GENERAL;
+    @Getter private final String message;
 
     public GeneralError(String message) {
         this.message = message;
diff --git a/lib/src/main/java/javasdk/exceptions/ParseError.java b/lib/src/main/java/javasdk/exceptions/ParseError.java
index 0e2a7245..aef9fa6a 100644
--- a/lib/src/main/java/javasdk/exceptions/ParseError.java
+++ b/lib/src/main/java/javasdk/exceptions/ParseError.java
@@ -5,6 +5,6 @@ import lombok.Getter;
 
 public class ParseError extends OpenFeatureError {
     @Getter
-    private ErrorCode errorCode = ErrorCode.PARSE_ERROR;
+    private final ErrorCode errorCode = ErrorCode.PARSE_ERROR;
 
 }
diff --git a/lib/src/main/java/javasdk/exceptions/TypeMismatchError.java b/lib/src/main/java/javasdk/exceptions/TypeMismatchError.java
index ed272ff0..c7a50586 100644
--- a/lib/src/main/java/javasdk/exceptions/TypeMismatchError.java
+++ b/lib/src/main/java/javasdk/exceptions/TypeMismatchError.java
@@ -5,6 +5,6 @@ import lombok.Getter;
 
 public class TypeMismatchError extends OpenFeatureError {
     @Getter
-    private ErrorCode errorCode = ErrorCode.TYPE_MISMATCH;
+    private final ErrorCode errorCode = ErrorCode.TYPE_MISMATCH;
 
 }