String Memory Internals | Javalobby

String Memory Internals | Javalobby

String object itself is rather cheap. It's the text it points to that consumes most of the memory

String is just a thin wrapper around char[] to preserve immutability

new String("abc") isn't really that expensive as the internal text representation is reused. But still avoid such construct.

When String is concatenated from constant values known at compile time, concatenation is done by the compiler, not by the JVM

substring() is tricky, but most importantly, it is very cheap, both in terms of used memory and run time (constant in both cases)

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