String concatenation as argument to 'StringBuilder.append()' call

Reports String concatenation used as the argument to StringBuffer.append(), StringBuilder.append() or Appendable.append().

Such calls may profitably be turned into chained append calls on the existing StringBuffer/Builder/Appendable saving the cost of an extra StringBuffer/Builder allocation. This inspection ignores compile-time evaluated String concatenations, in which case the conversion would only worsen performance.

Example:

  void bar(StringBuilder builder, String name) {
    builder.append("Hello," + name);    //warning
    builder.append("Hello," + "world"); //no warning
  }

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StringConcatenationInsideStringBufferAppend

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Inspection Details
By default bundled with:	IntelliJ IDEA 2024.2, Qodana for JVM 2024.2,
Can be installed with plugin:	Java, 242.22892

Last modified: 11 September 2024