Spring - Create bean based on Annotation field -

update: used different approach problem.

side-question: know how spring exclude in springbootapplication

the springbootapplication:

@target(elementtype.type) @retention(retentionpolicy.runtime) @documented @inherited @springbootconfiguration @enableautoconfiguration @componentscan(excludefilters = @filter(type = filtertype.custom, classes = typeexcludefilter.class)) public @interface springbootapplication { 

so when context loaded, , enableautoconfiguration executed, excludes available.

thats same want.

at bean-creation want know if annotation has field (for example boolean)

old question:

i have annotation:

@target(elementtype.type) @retention(retentionpolicy.runtime) @import(taskspringcontext.class) public @interface tasktest {     class<? extends databaseservice> db() default databaseservice.class; } 

this annotation used at:

@tasktest(db = databaseserviceextended.class) @springbootapplication() public class taskserver {      public static void main(string[] args)     {         final applicationcontext ctx = springapplication.run(taskserver.class, args);     }  } 

now, @ taskspringcontext.class want create bean based on db-field of tasktest-annotation:

@bean(name = "databaseservice") public databaseservice databaseservice() {     return ??     here want return databaseserviceextended } 

anyone knows how it?

i assume there's better way it, scan classpath, starting "com.example" classes annotated com.example.tasktest , add bean definition it, bean created later.

this allow check classes annotation, of course have solve problem 2 (or more) @tasktest on classpath.

@component public class testbeanprocessor implements beandefinitionregistrypostprocessor {      @override     public void postprocessbeanfactory(configurablelistablebeanfactory beanfactory) throws beansexception {         ; // nothing     }      @override     public void postprocessbeandefinitionregistry(beandefinitionregistry registry) throws beansexception {         set<beandefinition> definitions = scanforbeandefinitionsin("com.example"); // base package          // test if 1 or more, perhaps error, whatever          beandefinition def = ...; // 1 of them          class<?> clz = class.forname(def.getbeanclassname());         tasktest annotation = clz.getannotation(tasktest.class);          // create new rootbeandefinition tasktext data (pretty analogous xml)          rootbeandefinition datasourcedefinition = ...;          registry.registerbeandefinition("datasource", datasourcedefinition);     }      protected set<beandefinition> scanforbeandefinitionsin(string basepackage) {         classpathscanningcandidatecomponentprovider scanner = new classpathscanningcandidatecomponentprovider(false);         scanner.addincludefilter(new typefilter() {              @override             public boolean match(metadatareader metadatareader, metadatareaderfactory metadatareaderfactory) throws ioexception {                 return metadatareader.getannotationmetadata().getannotationtypes().contains("com.example.tasktest");             }          });              return scanner.findcandidatecomponents(basepackage);     } }