Adaptive (dubbo-all 2.6.10.1 API)

```
()
({,})
public @interface Adaptive
```
Provide helpful information for ExtensionLoader to inject dependency extension instance.

另请参阅:

ExtensionLoader, URL

- 可选元素概要
  
  可选元素
  修饰符和类型可选元素说明
  
  [] value
  Decide which target extension to be injected.

- 元素详细资料
  - value
```
[] value
```
    Decide which target extension to be injected. The name of the target extension is decided by the parameter passed in the URL, and the parameter names are given by this method.
    If the specified parameters are not found from URL, then the default extension will be used for dependency injection (specified in its interface's SPI).
    For examples, given String[] {"key1", "key2"}:
    
    find parameter 'key1' in URL, use its value as the extension's name
    
    try 'key2' for extension's name if 'key1' is not found (or its value is empty) in URL
    
    use default extension if 'key2' doesn't appear either
    
    otherwise, throw
    
    If default extension's name is not give on interface's SPI, then a name is generated from interface's class name with the rule: divide classname from capital char into several parts, and separate the parts with dot '.', for example: for com.alibaba.dubbo.xxx.YyyInvokerWrapper, its default name is String[] {"yyy.invoker.wrapper"}. This name will be used to search for parameter from URL.
    返回:
    
    parameter key names in URL
    
    默认值:
    
    {}