Empty String Concatenation for Type Conversion
ID |
java.string_concat_for_conversion |
Severity |
info |
Remediation Complexity |
medium |
Remediation Risk |
low |
Remediation Effort |
medium |
Resource |
Code Smell |
Language |
Java |
Tags |
best-practice, code-style |
Description
Reports the use of "" + x or x + "" to convert a value to a String. While functionally correct, this idiom is less readable than the explicit conversion methods and creates an unnecessary intermediate StringBuilder.
Rationale
Concatenating an empty string with a value is a common shortcut for converting the value to a String. However, it obscures the intent of the code. The reader has to recognize the pattern rather than seeing an explicit conversion call. Additionally, the compiler generates a StringBuilder to perform the concatenation, which is wasteful when the goal is simply to obtain a string representation.
// Bad -- empty-string concatenation for conversion
String s = "" + count;
String t = value + "";Remediation
Use String.valueOf(x) or the appropriate wrapper type’s toString() method for explicit, readable conversion.
// Good -- explicit conversion
String s = String.valueOf(count);
String t = Integer.toString(value);