JDK7有不少新东东, 语言特性里有一些更新, 虽然不如 JDK1.5 的泛型/可变参数/for-each循环那么激动人心, 但在平时开发中还是有很大帮助. 个人感觉 try 语句的新特性最有用. 参考: JSR-334
写篇文章记录一下.
public class CommonTest { public static void main(String[] args) { List< String> list = ["item"]; String item = list[0]; Set< String > set = {"item"}; Map< String,Integer > map = {"key" : 1}; int value = map["key"]; // try-with-resources statement try (InputStream in = System.in; OutputStream out = System.out) { // Binary integral literals and underscores in numeric literals int a = 32_242; int b = 0B011_101; int c = 023_273; int d = 0x23_2c_ab; // Improved Type Inference for Generic Instance Creation (diamond) List<String> aa = new ArrayList<>(); // Strings in switch String str = "str"; switch (str) { } // Multi-catch and more precise rethrow } catch (IllegalArgumentException | IndexOutOfBoundsException e) { } catch (IOException e) { } } // Simplified Varargs Method Invocation @SafeVarargs public static void f(List... t) { } }