Java: Add initial version of string replaceAll with no regex query

java/ql/src/Performance/StringReplaceAllWithNonRegex.md

@@ -0,0 +1,28 @@
+# J-STR-001: Use of `String.replaceAll` with a first argument of a non regular expression
+
+Using `String.replaceAll` is less performant than `String.replace` when the first argument is not a regular expression.
+
+## Overview
+
+The underlying implementation of `String.replaceAll` uses `Pattern.compile` and expects a regular expression as its first argument. However in cases where the argument could be represented by just a plain `String` that does not represent an interesting regular expression, a call to `String.replace` may be more performant as it does not need to compile the regular expression.
+
+## Recommendation
+
+Use `String.replace` instead where a `replaceAll` call uses a trivial string as its first argument.
+
+## Example
+
+```java
+public class Test {
+    void f() {
+        String s1 = "test";
+        s1 = s1.replaceAll("t", "x"); // NON_COMPLIANT
+        s1 = s1.replaceAll(".*", "x"); // COMPLIANT
+    }
+}
+
+```
+
+## References
+
+- [String.replaceAll](https://docs.oracle.com/en/java/javase/20/docs/api/java.base/java/lang/String.html#replaceAll(java.lang.String,java.lang.String))