What is the best way to append strings in Java?

General Discussions
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@joe-elmoufak raises a valid point about thread safety, but there’s another optimization trick for large-scale string operations—preallocating capacity in StringBuilder. This reduces unnecessary memory reallocations and boosts performance:"*

StringBuilder unicodeArray = new StringBuilder(1000);  // Preallocate space  
unicodeArray.append("u1234 u12de u1386 ... u15a3");  
unicodeArray.append(" ").append("u13a2");  
System.out.println(unicodeArray.toString());

:white_check_mark: Why this helps?

  • Preallocating avoids repetitive resizing, making appends faster.
  • Particularly useful when handling large text data in loops.
  • A must-know technique for efficient string append java operations.