Class CandidateComponentsIndex

java.lang.Object

org.springframework.context.index.CandidateComponentsIndex

public class CandidateComponentsIndex
extends Object

Provide access to the candidates that are defined in META-INF/spring.components component index files (see CandidateComponentsIndex(List)) or registered programmatically (see CandidateComponentsIndex()).

An arbitrary number of stereotypes can be registered (and queried) on the index: a typical example is the fully qualified name of an annotation that flags the class for a certain use case. The following call returns all the @Component candidate types for the com.example package (and its sub-packages):

Set<String> candidates = index.getCandidateTypes(
        "com.example", "org.springframework.stereotype.Component");

The type is usually the fully qualified name of a class, though this is not a rule. Similarly, the stereotype is usually the fully qualified name of an annotation type, but it can be any marker really.

Since:

5.0

Author:

Stephane Nicoll, Juergen Hoeller

Constructor Summary

Constructors

Constructor	Description
CandidateComponentsIndex()	Create a new index instance for programmatic population.

Method Summary

Modifier and Type	Method	Description
Set<String>	getCandidateTypes(String basePackage, String stereotype)	Return the candidate types that are associated with the specified stereotype.
Set<String>	getRegisteredScans()	Return the registered base packages (or base package patterns).
Set<String>	getRegisteredStereotypes()	Return the registered stereotype packages (or base package patterns).
boolean	hasScannedPackage(String packageName)	Determine whether this index contains an entry for the given base package (or base package pattern).
void	registerCandidateType(String type, String... stereotypes)	Programmatically register one or more stereotypes for the given candidate type.
void	registerScan(String... basePackages)	Programmatically register the given base packages (or base package patterns) as scanned.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CandidateComponentsIndex

public CandidateComponentsIndex()

Create a new index instance for programmatic population.

Since:

7.0

See Also:

• registerScan(String...)
• registerCandidateType(String, String...)

Method Details

registerScan

public void registerScan(String... basePackages)

Programmatically register the given base packages (or base package patterns) as scanned.

Since:

7.0

See Also:

• registerCandidateType(String, String...)

getRegisteredScans

public Set<String> getRegisteredScans()

Return the registered base packages (or base package patterns).

Since:

7.0

See Also:

• registerScan(String...)

hasScannedPackage

public boolean hasScannedPackage(String packageName)

Determine whether this index contains an entry for the given base package (or base package pattern).

Since:

7.0

registerCandidateType

public void registerCandidateType(String type,
 String... stereotypes)

Programmatically register one or more stereotypes for the given candidate type.

Note that the containing packages for candidates are not automatically considered scanned packages. Make sure to call registerScan(String...) with the scan-specific base package accordingly.

Since:

7.0

See Also:

• registerScan(String...)

getRegisteredStereotypes

public Set<String> getRegisteredStereotypes()

Return the registered stereotype packages (or base package patterns).

Since:

7.0

getCandidateTypes

public Set<String> getCandidateTypes(String basePackage,
 String stereotype)

Return the candidate types that are associated with the specified stereotype.

Parameters:

basePackage - the package to check for candidates

stereotype - the stereotype to use

Returns:

the candidate types associated with the specified stereotype or an empty set if none has been found for the specified basePackage