From 3fdbf7d6cbaaa78f2edc2f48922beeb5c2e4a9ce Mon Sep 17 00:00:00 2001
From: Andreas Dangel <andreas.dangel@pmd-code.org>
Date: Thu, 14 Nov 2024 17:48:08 +0100
Subject: [PATCH] [java] InsufficientStringBufferDeclaration: Fix CCE for
 Character

Fixes #5314
---
 docs/pages/release_notes.md                   |  2 ++
 ...sufficientStringBufferDeclarationRule.java |  8 +++++++-
 .../InsufficientStringBufferDeclaration.xml   | 19 +++++++++++++++++++
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/docs/pages/release_notes.md b/docs/pages/release_notes.md
index 5fa3ac04b6..3893f1a820 100644
--- a/docs/pages/release_notes.md
+++ b/docs/pages/release_notes.md
@@ -20,6 +20,8 @@ This is a {{ site.pmd.release_type }} release.
 * java
   * [#5293](https://github.com/pmd/pmd/issues/5293): \[java] Deadlock when executing PMD in multiple threads
   * [#5324](https://github.com/pmd/pmd/issues/5324): \[java] Issue with type inference of nested lambdas
+* java-performance
+  * [#5314](https://github.com/pmd/pmd/issues/5314): \[java] InsufficientStringBufferDeclarationRule: Lack of handling for char type parameters
 
 ### 🚨 API Changes
 
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/performance/InsufficientStringBufferDeclarationRule.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/performance/InsufficientStringBufferDeclarationRule.java
index a6fabf91a2..5acd063c15 100644
--- a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/performance/InsufficientStringBufferDeclarationRule.java
+++ b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/performance/InsufficientStringBufferDeclarationRule.java
@@ -240,6 +240,12 @@ public class InsufficientStringBufferDeclarationRule extends AbstractJavaRulecha
 
     private int calculateExpression(ASTExpression expression) {
         Object value = expression.getConstValue();
-        return value == null ? State.UNKNOWN_CAPACITY : (Integer) value;
+        if (value == null) {
+            return State.UNKNOWN_CAPACITY;
+        }
+        if (value instanceof Character) {
+            return (Character) value;
+        }
+        return (Integer) value;
     }
 }
diff --git a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/InsufficientStringBufferDeclaration.xml b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/InsufficientStringBufferDeclaration.xml
index ec267fcfcc..bd5d364eb1 100644
--- a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/InsufficientStringBufferDeclaration.xml
+++ b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/InsufficientStringBufferDeclaration.xml
@@ -1419,4 +1419,23 @@ public class LiteralExpression {
 }
         ]]></code>
     </test-code>
+
+    <test-code>
+        <description>#5314 [java] InsufficientStringBufferDeclarationRule: Lack of handling for char type parameters</description>
+        <expected-problems>0</expected-problems>
+        <code><![CDATA[
+public class StringBufferInstantiationWithCharTest {
+    public void example01() {
+        // misleading instantiation, these buffers
+        // are actually sized to 99 characters long
+        StringBuffer  sb1 = new StringBuffer('c');
+        StringBuilder sb2 = new StringBuilder('c');
+
+        // in these forms, just single characters are allocated
+        StringBuffer  sb3 = new StringBuffer("c");
+        StringBuilder sb4 = new StringBuilder("c");
+    }
+}
+]]></code>
+    </test-code>
 </test-data>