1,switch中可以使用字串了String s = "test"; switch (s)
{ case "test" : System.out.println("test");
case "test1" : System.out.println("test1");
break ;
default : System.out.println("break");
break ;
}
2.运用List<String> tempList = new ArrayList<>();
即泛型实例化类型自动推断3.语法上支持集合,而不一定是数组final List<Integer> piDigits = [ 1,2,3,4,5,8 ];
4.新增一些取环境信息的工具方法File System.getJavaIoTempDir() // IO临时文件夹File System.getJavaHomeDir() // JRE的安装目录File System.getUserHomeDir()
// 当前用户目录File System.getUserDir() // 启动java进程时所在的目录55.Boolean类型反转,空指针安全,参与位运算Boolean Booleans.negate(Boolean booleanObj)True => False , False => True, Null => Nullboolean Booleans.and(boolean[] array)boolean Booleans.or(boolean[] array)boolean Booleans.xor(boolean[] array)boolean Booleans.and(Boolean[] array)boolean Booleans.or(Boolean[] array)boolean Booleans.xor(Boolean[] array)
6.两个char间的equals boolean Character.equalsIgnoreCase(char ch1, char ch2)
7.安全的加减乘除 int Math.safeToInt(long value)int Math.safeNegate(int value)long Math.safeSubtract(long value1, int value2)long Math.safeSubtract(long value1, long value2)int Math.safeMultiply(int value1, int value2)long Math.safeMultiply(long value1, int value2)long Math.safeMultiply(long value1, long value2)long Math.safeNegate(long value)int Math.safeAdd(int value1, int value2)long Math.safeAdd(long value1, int value2)long Math.safeAdd(long value1, long value2)int Math.safeSubtract(int value1, int value2)
8.map集合支持并发请求,且可以写成 Map map = {name:"xxx",age:18}; |