@PathVariable("ownerId") String theOwner 和@PathVariable String theOwner 的区别

Question

@PathVariable("ownerId") String theOwner和Spring MVC中的@PathVariable String theOwner有区别吗？

我已经完成了 Spring @PathVariable，但我不清楚这个概念。

我通过分析 uri parameter 是否与 variable name 具有相同的名称发现了一个区别，那么您可以直接将其存储在变量中。这是否正确，或者您可以 post 与此相关的任何其他信息。

@GetMapping("/owners/{ownerId}")
public String findOwner(@PathVariable("ownerId") String theOwner, Model model) {
// implementation omitted
}

@GetMapping("/owners/{ownerId}")
public String findOwner(@PathVariable String ownerId, Model model) {
// implementation omitted
}

Answer 1

唯一的区别是第一个选项允许您更改方法中的参数名称，您可以使用 theOwner 而不是 ownerId。

这可能很有用，例如，如果您有一个 class 成员同名 ownerId

Answer 2

来自您提到的文档页面：

The URI Template "/owners/{ownerId}" specifies the variable name `ownerId. When the controller handles this request, the value of ownerId is set to the value found in the appropriate part of the URI. For example, when a request comes in for /owners/fred, the value of ownerId is fred.

因此，如果您不想指定 @PathVariable 的值，请在您的方法参数和路径模板中使用相同的名称。

Answer 3

Spring MVC documentation 非常清楚它是如何工作的：

To process the @PathVariable annotation, Spring MVC needs to find the matching URI template variable by name. You can specify it in the annotation:
@GetMapping("/owners/{ownerId}")
public String findOwner(@PathVariable("ownerId") String theOwner, Model model) {
    // implementation omitted
}
Or if the URI template variable name matches the method argument name you can omit that detail. As long as your code is compiled with debugging information or the -parameters compiler flag on Java 8, Spring MVC will match the method argument name to the URI template variable name:
@GetMapping("/owners/{ownerId}")
public String findOwner(@PathVariable String ownerId, Model model) {
    // implementation omitted
}

@PathVariable("ownerId") String theOwner 和@PathVariable String theOwner 的区别

Difference between @PathVariable("ownerId") String theOwner and @PathVariable String theOwner

java

spring

path-variables

spring-mvc