Code simplification

1.1. Using ternary expressions
2. from Java 5 rise , Provides for-each loop , Simplify the circular traversal of arrays and collections . for-each You don't need to allow the tradition for The index in the loop can traverse the array , Or when using iterators, you don't need to while Cyclic invocation hasNext Methods and next Method can traverse the collection .

1.4. utilize return keyword

utilize static keyword , You can turn a field into a static field , You can also turn a function into a static function , When called, there is no need to initialize the class object .

1.6. utilize lambda expression

Static import （import static）, When the same static constants and functions are widely used in the program , You can simplify references to static constants and functions .

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