org.springframework.web.servlet.resource

Class FixedVersionStrategy

java.lang.Object

org.springframework.web.servlet.resource.AbstractVersionStrategy

org.springframework.web.servlet.resource.FixedVersionStrategy

All Implemented Interfaces:

VersionStrategy

public class FixedVersionStrategy
extends AbstractVersionStrategy

A VersionStrategy that handles unique, static, application-wide version strings as prefixes in the request path.

Enables inserting a unique and static version String (e.g. reduced SHA, version name, release date) at the beginning of resource paths so that when a new version of the application is released, clients are forced to reload application resources.

This is useful when changing resource names is not an option (e.g. when using JavaScript module loaders). If that's not the case, the use of ContentBasedVersionStrategy provides more optimal performance since version is generated on a per-resource basis: only actually modified resources are reloaded by the client.

Since:

4.1

Author:

Brian Clozel, Sam Brannen

See Also:

VersionResourceResolver

Field Summary

Fields inherited from class org.springframework.web.servlet.resource.AbstractVersionStrategy

logger

Constructor Summary

Constructors

Constructor and Description
FixedVersionStrategy(Callable<String> versionInitializer) Create a new FixedVersionStrategy and get the version string to use by calling the given Callable instance.
FixedVersionStrategy(String fixedVersion) Create a new FixedVersionStrategy with the given version string.

Method Summary

Modifier and Type	Method and Description
String	addVersionToUrl(String baseUrl, List<? extends org.springframework.core.io.Resource> locations, ResourceResolverChain chain) Adds a version string to the given baseUrl.
String	deleteVersionFromPath(String requestPath, String candidateVersion) Deletes the given candidate version string from the given request path.
String	extractVersionFromPath(String requestPath) Extracts a version string from the request path.
boolean	resourceVersionMatches(org.springframework.core.io.Resource baseResource, String candidateVersion) Checks whether the given Resource matches the candidate version string.

Methods inherited from class org.springframework.web.servlet.resource.AbstractVersionStrategy

addVersionAsPrefix, addVersionToFilename, deleteVersionAsPrefix, deleteVersionFromFilename, extractVersionAsPrefix, extractVersionFromFilename

Methods inherited from class java.lang.Object

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

Constructor Detail

FixedVersionStrategy

public FixedVersionStrategy(String fixedVersion)

Create a new FixedVersionStrategy with the given version string.

Parameters:

fixedVersion - the fixed version string to use

FixedVersionStrategy

public FixedVersionStrategy(Callable<String> versionInitializer)
                     throws Exception

Create a new FixedVersionStrategy and get the version string to use by calling the given Callable instance.

Throws:

Exception

Method Detail

extractVersionFromPath

public String extractVersionFromPath(String requestPath)

Description copied from interface: VersionStrategy

Extracts a version string from the request path.

Parameters:

requestPath - the request path of the resource being resolved

Returns:

the version string or an empty string if none was found

deleteVersionFromPath

public String deleteVersionFromPath(String requestPath,
                                    String candidateVersion)

Description copied from interface: VersionStrategy

Deletes the given candidate version string from the given request path.

Parameters:

requestPath - the request path of the resource being resolved

candidateVersion - the candidate version string

Returns:

the modified request path, without the version string

resourceVersionMatches

public boolean resourceVersionMatches(org.springframework.core.io.Resource baseResource,
                                      String candidateVersion)

Description copied from interface: VersionStrategy

Checks whether the given Resource matches the candidate version string. Useful when the version string is managed on a per-resource basis.

Parameters:

baseResource - the resource to check against the given version

candidateVersion - the candidate version for the given resource

Returns:

true if the resource matches the version string, false otherwise

addVersionToUrl

public String addVersionToUrl(String baseUrl,
                              List<? extends org.springframework.core.io.Resource> locations,
                              ResourceResolverChain chain)

Description copied from interface: VersionStrategy

Adds a version string to the given baseUrl.

Parameters:

baseUrl - the baseUrl of the requested resource

locations - the resource locations to resolve resources from

chain - the chain of resource resolvers

Returns:

the baseUrl updated with a version string