Spring @Value with arraylist 拆分并获取第一个值

Question

Spring @Valuewith arraylist split并获取arrayList的第一个值

我有my.list=a,b,c

我正在努力获得第一个价值，即

我试过，

@Value("#{'${my.list}'.split(',')})

List<String> values;

String myVal = values.get(0);

有没有比这个过程更好的方法？

Answer 1

你在这一行有语法错误@Value("#{'${my.list}'.split(',')})应该更正如下@Value("#{'${my.list}'.split(',')}")List<String> values;我建议您使用以下解决方案作为更好的方法领域类@Componentpublic class Data {&nbsp; &nbsp; @Value("#{'${my.list}'.split(',')}")&nbsp; &nbsp; List<String> values;&nbsp; &nbsp; public List<String> getValues() {&nbsp; &nbsp; &nbsp; &nbsp; return values;&nbsp; &nbsp; }&nbsp; &nbsp; public void setValues(List<String> values) {&nbsp; &nbsp; &nbsp; &nbsp; this.values = values;&nbsp; &nbsp; }}这就是你如何使用域类@RestController@RequestMapping("/")public class Mycon {&nbsp; &nbsp; @Autowired&nbsp; &nbsp; Data data;&nbsp; &nbsp; @GetMapping&nbsp; &nbsp; public String hello(ModelMap model) {&nbsp; &nbsp; &nbsp; &nbsp; return data.getValues().get(0);&nbsp; &nbsp; }}application.properties 文件my.list=a,b,c您可以直接使用该值，如下所示@Value("#{'${my.list}'.split(',')[0]}")String values;

Answer 2

@AutowiredEnvironment env;//To get the List<String>List<String> values = Arrays.asList(env.getProperty("my.list").split(",");//Then, you can get value into an Optional to prevent NullPointerExceptionOptional<String> myValue = values.stream().findFirst();