Performance optimizations for Java

Method areas in the JVM:

The Permanent zone---information about the stored class. Method. Constant. static variables

Performance optimization for 1.Java

1. Reduce GC pressure, priority is lower than the thread, he is a daemon thread

Reclaim our heap of memory.

2. Try to avoid our new operation

1.string,stringbuffer,stringbuilder

String immutable length of the class an immutable character array.

2.for foreach while iterator.

The type array after foreach and this efficiency is the slowest one in later code is best used for loops

3. Use the basic data type as much as possible.

4. Use local variables as much as possible.

5. The fewer code in the synchronization code block, the better

6. Multi-use final cosmetic class. Prevents the method from being overridden.

Performance optimizations for Java