1.对collections的支持

List<String> list = new ArrayList<String>(); list.add("item"); String item = list.get(0);  Set<String> set = new HashSet<String>(); set.add("item");  Map<String, Integer> map = new HashMap<String, Integer>(); map.put("key", 1); int value = map.get("key");

 现在你还可以：

List<String> list = ["item"]; String item = list[0];  Set<String> set = {"item"};  Map<String, Integer> map = {"key" : 1}; int value = map["key"]; 

2.自动资源管理

BufferedReader br = new BufferedReader(new FileReader(path)); try {    return br.readLine(); } finally {    br.close(); } 

 becomes:

try (BufferedReader br = new BufferedReader(new FileReader(path)) {    return br.readLine(); }  You can declare more than one resource to close:  try (    InputStream in = new FileInputStream(src);    OutputStream out = new FileOutputStream(dest)) {  // code }

3.对通用实例创建(diamond)的type引用进行了改进

Map<String, List<String>> anagrams = new HashMap<String, List<String>>();  

 becomes:

Map<String, List<String>> anagrams = new HashMap<>();

4.数值可加下划线

int one_million = 1_000_000;

5.在switch中可使用string

String s = ... switch(s) {  case "quux":     processQuux(s);     // fall-through    case "foo":   case "bar":     processFooOrBar(s);     break;    case "baz":      processBaz(s);     // fall-through    default:     processDefault(s);     break; } 

6.二进制文字

int binary = 0b1001_1001;

7.简化了可变参数方法的调用

当程序员试图使用一个不可具体化的可变参数并调用一个*varargs* （可变）方法时，编辑器会生成一个“非安全操作”的警告