From f805e7009add0d9512c70956569ea00f11fa42f9 Mon Sep 17 00:00:00 2001
From: Mina Asham <mina.asham@hotmail.com>
Date: Mon, 10 Feb 2025 19:59:51 +0000
Subject: [PATCH] fix: Avoid creating message string prematurely for streaming
 calls (#3622)
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- Creating the string message prematurely puts a lot of strain on the
JVM and GC, switch to the format version of `Preconditions.checkState`
which only constructs the string if we throw the exception
- Issue: https://github.com/googleapis/sdk-platform-java/issues/3621

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Fixes #3621 ☕️
---
 .../google/api/gax/rpc/StateCheckingResponseObserver.java | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/gax-java/gax/src/main/java/com/google/api/gax/rpc/StateCheckingResponseObserver.java b/gax-java/gax/src/main/java/com/google/api/gax/rpc/StateCheckingResponseObserver.java
index d787f434dc..fab764f4f2 100644
--- a/gax-java/gax/src/main/java/com/google/api/gax/rpc/StateCheckingResponseObserver.java
+++ b/gax-java/gax/src/main/java/com/google/api/gax/rpc/StateCheckingResponseObserver.java
@@ -43,7 +43,7 @@ public abstract class StateCheckingResponseObserver<V> implements ResponseObserv
    * ensuring consistent state.
    */
   public final void onStart(StreamController controller) {
-    Preconditions.checkState(!isStarted, getClass() + " is already started.");
+    Preconditions.checkState(!isStarted, "%s is already started.", getClass());
     isStarted = true;
 
     onStartImpl(controller);
@@ -56,7 +56,7 @@ public final void onStart(StreamController controller) {
    * consistent state.
    */
   public final void onResponse(V response) {
-    Preconditions.checkState(!isClosed, getClass() + " received a response after being closed.");
+    Preconditions.checkState(!isClosed, "%s received a response after being closed.", getClass());
     onResponseImpl(response);
   }
 
@@ -67,7 +67,7 @@ public final void onResponse(V response) {
    * state.
    */
   public final void onComplete() {
-    Preconditions.checkState(!isClosed, getClass() + " tried to double close.");
+    Preconditions.checkState(!isClosed, "%s tried to double close.", getClass());
     isClosed = true;
     onCompleteImpl();
   }
@@ -79,7 +79,7 @@ public final void onComplete() {
    * consistent state.
    */
   public final void onError(Throwable t) {
-    Preconditions.checkState(!isClosed, getClass() + " received error after being closed", t);
+    Preconditions.checkState(!isClosed, "%s received error after being closed", t, getClass());
     isClosed = true;
     onErrorImpl(t);
   }