The @Resource and @AutoWired annotations are both used for Bean injection, with the most obvious difference being that @AutoWired is a Spring-provided annotation. @Resource is not a Spring annotation, but Spring supports the injection of this annotation.
Here are the specific differences between the two annotations:
@Autowired
@autowired. ByType injection by default. If there are more than one of the same types, match by byName. If the bean does not match, an error is reported.
The @autowired annotation is used with the @Qualifier annotation to specify a variable name, and the @Autowired annotation will be injected as byName by default.
@Resource
@resource is automatically injected by byName by default. The @resource has two properties that are important: name and type. Spring resolves the name attribute of the @Resource annotation to the bean name, and the Type attribute to the bean type.
So if the name attribute is used, the byName auto-injection policy is used, and if the Type attribute is used, the byType auto-injection policy is used. If neither name nor type attributes are specified, the byName automatic injection policy is used through reflection.
@resource Assembly sequence:
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If both name and Type are specified, a unique matching bean is found from the Spring context and assembled, failing which an exception is thrown
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If name is specified, the bean whose name (ID) matches is searched from the context for assembly, and an exception is thrown if no bean is found
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If type is specified, an exception will be thrown if a unique bean whose type matches is found in the context and assembly is performed
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If neither name nor type is specified, byName is automatically used for assembly. If there is no match, the system backs up to a primitive type for matching. If there is a match, automatic assembly is performed. Back to primitive type (byType match)
conclusion
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The @autowired annotation starts byType and then byName matches
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The @resource annotation starts byName and then byType matches