org.springframework.context.index

Class CandidateComponentsIndexLoader

java.lang.Object

org.springframework.context.index.CandidateComponentsIndexLoader

public final class CandidateComponentsIndexLoader
extends java.lang.Object

Candidate components index loading mechanism for internal use within the framework.

Since:

5.0

Author:

Stephane Nicoll

Field Summary

Fields

Modifier and Type	Field and Description
private static java.util.concurrent.ConcurrentMap<java.lang.ClassLoader,CandidateComponentsIndex>	cache
static java.lang.String	COMPONENTS_RESOURCE_LOCATION The location to look for components.
static java.lang.String	IGNORE_INDEX System property that instructs Spring to ignore the index, i.e.
private static Log	logger
private static boolean	shouldIgnoreIndex

Constructor Summary

Constructors

Modifier	Constructor and Description
private	CandidateComponentsIndexLoader()

Method Summary

Modifier and Type	Method and Description
private static CandidateComponentsIndex	doLoadIndex(java.lang.ClassLoader classLoader)
static CandidateComponentsIndex	loadIndex(java.lang.ClassLoader classLoader) Load and instantiate the CandidateComponentsIndex from "META-INF/spring.components", using the given class loader.

Methods inherited from class java.lang.Object

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

Field Detail

COMPONENTS_RESOURCE_LOCATION

public static final java.lang.String COMPONENTS_RESOURCE_LOCATION

The location to look for components.

Can be present in multiple JAR files.

See Also:

Constant Field Values

IGNORE_INDEX

public static final java.lang.String IGNORE_INDEX

System property that instructs Spring to ignore the index, i.e. to always return null from loadIndex(ClassLoader).

The default is "false", allowing for regular use of the index. Switching this flag to true fulfills a corner case scenario when an index is partially available for some libraries (or use cases) but couldn't be built for the whole application. In this case, the application context fallbacks to a regular classpath arrangement (i.e. as no index was present at all).

See Also:

Constant Field Values

shouldIgnoreIndex

private static final boolean shouldIgnoreIndex

logger

private static final Log logger

cache

private static final java.util.concurrent.ConcurrentMap<java.lang.ClassLoader,CandidateComponentsIndex> cache

Constructor Detail

CandidateComponentsIndexLoader

private CandidateComponentsIndexLoader()

Method Detail

loadIndex

@Nullable
public static CandidateComponentsIndex loadIndex(@Nullable
                                                           java.lang.ClassLoader classLoader)

Load and instantiate the CandidateComponentsIndex from "META-INF/spring.components", using the given class loader. If no index is available, return null.

Parameters:

classLoader - the ClassLoader to use for loading (can be null to use the default)

Returns:

the index to use or null if no index was found

Throws:

java.lang.IllegalArgumentException - if any module index cannot be loaded or if an error occurs while creating CandidateComponentsIndex

doLoadIndex

@Nullable
private static CandidateComponentsIndex doLoadIndex(java.lang.ClassLoader classLoader)