From 92bf80f3e4dff7b1f3edaa32c5979b415d5a5954 Mon Sep 17 00:00:00 2001
From: Cheng Xing <u7729914@anu.edu.au>
Date: Sun, 20 Oct 2024 00:05:06 +1100
Subject: [PATCH 1/3] Add isMemoized() method to MemoizingSupplier -allowing
 check whether the value has been memoized without triggering the memoization
 process. -updated toString() to reflect state

Resolves issue#7292
---
 guava/src/com/google/common/base/Suppliers.java | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/guava/src/com/google/common/base/Suppliers.java b/guava/src/com/google/common/base/Suppliers.java
index 9476c21872fc..1d9a6e6939e6 100644
--- a/guava/src/com/google/common/base/Suppliers.java
+++ b/guava/src/com/google/common/base/Suppliers.java
@@ -154,11 +154,18 @@ public T get() {
       return uncheckedCastNullableTToT(value);
     }
 
+    /**
+     * Returns whether the value has been memoized without triggering memoization.
+     */
+    public boolean isMemoized() {
+      return initialized;
+    }
+
     @Override
     public String toString() {
       return "Suppliers.memoize("
-          + (initialized ? "<supplier that returned " + value + ">" : delegate)
-          + ")";
+              + (initialized ? "<supplier that returned " + value + ">" : delegate)
+              + ")";
     }
 
     @GwtIncompatible // serialization
@@ -171,6 +178,7 @@ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundE
     private static final long serialVersionUID = 0;
   }
 
+
   @VisibleForTesting
   static class NonSerializableMemoizingSupplier<T extends @Nullable Object> implements Supplier<T> {
     private final Object lock = new Object();

From 16ebce0ae97b9dc62a23dfcb65cd249801319f54 Mon Sep 17 00:00:00 2001
From: Cheng Xing <u7729914@anu.edu.au>
Date: Sun, 20 Oct 2024 00:17:47 +1100
Subject: [PATCH 2/3] Add reset() and getIfMemoized() method to
 MemoizingSupplier - reset() method allowing resetting the cached value,
 enabling the supplier to recompute the value. - getIfMemoized() method
 returns the cached value if has been initialized, otherwise returns null.

Resolves issue#7292
---
 .../src/com/google/common/base/Suppliers.java | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/guava/src/com/google/common/base/Suppliers.java b/guava/src/com/google/common/base/Suppliers.java
index 1d9a6e6939e6..478f78fa378d 100644
--- a/guava/src/com/google/common/base/Suppliers.java
+++ b/guava/src/com/google/common/base/Suppliers.java
@@ -161,6 +161,26 @@ public boolean isMemoized() {
       return initialized;
     }
 
+    /**
+     * Resets the memoized value, allowing the supplier to recompute its value.
+     * This can be useful in cases where the value needs to be refreshed.
+     */
+    public void reset() {
+      synchronized (lock) {
+        initialized = false;
+        value = null;
+      }
+    }
+
+    /**
+     * Returns the memoized value if it has been initialized, otherwise returns {@code null}.
+     * This method does not trigger memoization.
+     */
+    @CheckForNull
+    public T getIfMemoized() {
+      return initialized ? value : null;
+    }
+
     @Override
     public String toString() {
       return "Suppliers.memoize("
@@ -179,6 +199,7 @@ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundE
   }
 
 
+
   @VisibleForTesting
   static class NonSerializableMemoizingSupplier<T extends @Nullable Object> implements Supplier<T> {
     private final Object lock = new Object();

From 29ac5c21bed61d67d3e9a551e8a3782fd48d14bc Mon Sep 17 00:00:00 2001
From: Cheng Xing <u7729914@anu.edu.au>
Date: Sun, 20 Oct 2024 00:40:45 +1100
Subject: [PATCH 3/3] Add refresh() method to MemoizingSupplier - refresh()
 which forces the recomputation of the cached value even if it has already
 been memoized. This will ensure the value is up to date.

Resolves issue#7292
---
 guava/src/com/google/common/base/Suppliers.java | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/guava/src/com/google/common/base/Suppliers.java b/guava/src/com/google/common/base/Suppliers.java
index 478f78fa378d..74d632df8c21 100644
--- a/guava/src/com/google/common/base/Suppliers.java
+++ b/guava/src/com/google/common/base/Suppliers.java
@@ -181,6 +181,21 @@ public T getIfMemoized() {
       return initialized ? value : null;
     }
 
+    /**
+     * Attempts to refresh the memoized value by recomputing it. This method forces recomputation
+     * even if the value was previously memoized, and it can be used to ensure the value is up to date.
+     * The recomputation occurs only if the current thread successfully acquires the lock.
+     */
+    public void refresh() {
+      synchronized (lock) {
+        T oldValue = value;
+        value = delegate.get();
+        initialized = true;
+        if (!value.equals(oldValue)) {
+          System.out.println("Memoized value has been refreshed from " + oldValue + " to " + value);
+        }
+      }
+    }
     @Override
     public String toString() {
       return "Suppliers.memoize("