COMP 202 Lecture Notes - Lecture 20: Concatenation

• School: McGill University
• Department: Computer Science (Sci)
• Course: COMP 202
• Professor: Melanie Lyman- Abramovitch

Document Summary

Strings are not primitive types, even if we"ve been using them as if they were. Arrays are regular reference types -- some people call them mutable . Immutable : you can not change the contents of a variable of type string after creating it. But we kind of feel like we have done this String phrase = cats ; phrase = phrase + dogs ; It looks like we are changing the value of a string after creating it! Immutable reference types are more secure, and more intuitive to use. Their behavior essentially mimics the behavior of primitive types. Midterm review (questions people got wrong) int[][] a = {{1,2,3}, {1,2}, null, {4,5,6,7}}; for(int i=0; i