Create LateInitValue:;computeIfUninitialized

Glavo · May 16, 2024 · e4afd57 · e4afd57
1 parent 6ae226b
commit e4afd57
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Showing 2 changed files with 40 additions and 4 deletions.
diff --git a/kala-base/src/main/java/kala/value/LateInitValue.java b/kala-base/src/main/java/kala/value/LateInitValue.java
@@ -15,10 +15,16 @@
  */
 package kala.value;
 
+import java.util.function.Supplier;
+
 public final class LateInitValue<T> implements Value<T> {
     private volatile boolean initialized = false;
     private T value;
 
+    public boolean isInitialized() {
+        return initialized;
+    }
+
     public void initialize(T value) {
         if (initialized) {
             throw new IllegalStateException("Value is initialized");
@@ -32,8 +38,18 @@ public void initialize(T value) {
         }
     }
 
-    public boolean isInitialized() {
-        return initialized;
+    public T computeIfUninitialized(Supplier<? extends T> supplier) {
+        if (initialized) {
+            return value;
+        }
+
+        synchronized (this) {
+            if (initialized) {
+                return value;
+            }
+
+            return value = supplier.get();
+        }
     }
 
     @Override

diff --git a/kala-base/src/main/template/kala/value/primitive/LateInitPrimitiveValue.java.ftl b/kala-base/src/main/template/kala/value/primitive/LateInitPrimitiveValue.java.ftl
@@ -15,10 +15,20 @@
  */
 package kala.value.primitive;
 
+<#if IsSpecialized || Type == "Boolean">
+import java.util.function.${Type}Supplier;
+<#else>
+import kala.function.${Type}Supplier;
+</#if>
+
 public final class LateInit${Type}Value extends Abstract${Type}Value implements ${Type}Value {
     private volatile boolean initialized = false;
     private ${PrimitiveType} value;
 
+    public boolean isInitialized() {
+        return initialized;
+    }
+
     public void initialize(${PrimitiveType} value) {
         if (initialized) {
             throw new IllegalStateException("Value is initialized");
@@ -32,8 +42,18 @@ public final class LateInit${Type}Value extends Abstract${Type}Value implements
         }
     }
 
-    public boolean isInitialized() {
-        return initialized;
+    public ${PrimitiveType} computeIfUninitialized(${Type}Supplier supplier) {
+        if (initialized) {
+            return value;
+        }
+
+        synchronized (this) {
+            if (initialized) {
+                return value;
+            }
+
+            return value = supplier.getAs${Type}();
+        }
     }
 
     @Override