WebappTemplateLoader (FreeMarker 2.3.23 API)

java.lang.Object
+
- freemarker.cache.WebappTemplateLoader
+

+
+
All Implemented Interfaces:
+
TemplateLoader
+
+
+
+
```
public class WebappTemplateLoader
+extends Object
+implements TemplateLoader
```
+
A TemplateLoader that uses streams reachable through ServletContext.getResource(String) as its source + of templates.
+

+ +

Constructor Summary

+ + + + + + + + + + + +

Constructors
Constructor and Description
`WebappTemplateLoader(javax.servlet.ServletContext servletContext)` + Creates a resource template cache that will use the specified servlet context to load the resources. +
`WebappTemplateLoader(javax.servlet.ServletContext servletContext, + String subdirPath)` + Creates a template loader that will use the specified servlet context to load the resources. +

+ +

+ + +

Method Summary

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`closeTemplateSource(Object templateSource)` + Closes the template source, releasing any resources held that are only required for reading the template and/or + its metadata. +
`Object`	`findTemplateSource(String name)` + Finds the template in the backing storage and returns an object that identifies the storage location where the + template can be loaded from. +
`boolean`	`getAttemptFileAccess()` + Getter pair of `setAttemptFileAccess(boolean)`. +
`long`	`getLastModified(Object templateSource)` + Returns the time of last modification of the specified template source. +
`Reader`	`getReader(Object templateSource, + String encoding)` + Returns the character stream of a template represented by the specified template source. +
`Boolean`	`getURLConnectionUsesCaches()` + Getter pair of `setURLConnectionUsesCaches(Boolean)`. +
`void`	`setAttemptFileAccess(boolean attemptLoadingFromFile)` + Specifies that before loading templates with `ServletContext.getResource(String)`, it should try to load + the template as `File`; default is `true`, though it's not always recommended anymore. +
`void`	`setURLConnectionUsesCaches(Boolean urlConnectionUsesCaches)` + It does the same as `URLTemplateLoader.setURLConnectionUsesCaches(Boolean)`; see there. +
`String`	`toString()` + Show class name and some details that are useful in template-not-found errors. +

+ + +
Methods inherited from class java.lang.Object
+clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

+ +
- + + +
  Constructor Detail
  + + + +
  - +
    WebappTemplateLoader
    +
```
public WebappTemplateLoader(javax.servlet.ServletContext servletContext)
```
    +
    Creates a resource template cache that will use the specified servlet context to load the resources. It will use + the base path of "/" meaning templates will be resolved relative to the servlet context root + location.
    +
    +
    Parameters:
    +
    servletContext - the servlet context whose ServletContext.getResource(String) will be used to load the + templates.
    +
    +
  + + + +
  - +
    WebappTemplateLoader
    +
```
public WebappTemplateLoader(javax.servlet.ServletContext servletContext,
+                            String subdirPath)
```
    +
    Creates a template loader that will use the specified servlet context to load the resources. It will use the + specified base path, which is interpreted relatively to the context root (does not mater if you start it with "/" + or not). Path components should be separated by forward slashes independently of the separator character used by + the underlying operating system.
    +
    +
    Parameters:
    +
    servletContext - the servlet context whose ServletContext.getResource(String) will be used to load the + templates.
    +
    subdirPath - the base path to template resources.
    +
    +
  +
+ +
- + + +
  Method Detail
  + + + +
  - +
    findTemplateSource
    +
```
public Object findTemplateSource(String name)
+                          throws IOException
```
    +
    Description copied from interface: TemplateLoader
    +
    Finds the template in the backing storage and returns an object that identifies the storage location where the + template can be loaded from. See the return value for more information.
    +
    +
    Specified by:
    +
    findTemplateSource in interface TemplateLoader
    +
    Parameters:
    +
    name - The name of the template, already localized and normalized by the + cache. It is completely up to the loader implementation to + interpret the name, however it should expect to receive hierarchical paths where path components are + separated by a slash (not backslash). Backslashes (or any other OS specific separator character) are + not considered as separators by FreeMarker, and thus they will not be replaced with slash before + passing to this method, so it's up to the template loader to handle them (say, be throwing and + exception that tells the user that the path (s)he has entered is invalid, as (s)he must use slash -- + typical mistake of Windows users). The passed names are always considered relative to some + loader-defined root location (often referred as the "template root directory"), and will never start + with a slash, nor will they contain a path component consisting of either a single or a double dot -- + these are all resolved by the template cache before passing the name to the loader. As a side effect, + paths that trivially reach outside template root directory, such as ../my.ftl, will be + rejected by the template cache, so they never reach the template loader. Note again, that if the path + uses backslash as path separator instead of slash as (the template loader should not accept that), the + normalization will not properly happen, as FreeMarker (the cache) recognizes only the slashes as + separators.
    +
    Returns:
    +
    An object representing the template source, which can be supplied in subsequent calls to + TemplateLoader.getLastModified(Object) and TemplateLoader.getReader(Object, String), when those are called on the + same TemplateLoader. null must be returned if the source for the template doesn't exist; + don't throw exception then! The exact type of this object is up to the TemplateLoader + implementation. As this object is possibly used as hash key in caches, and is surly compared with another + template source for equality, it must have a proper Object.equals(Object) and + Object.hashCode()) implementation. Especially, template sources that refer to the same + physical source must be equivalent, otherwise template caching can become inefficient. This is only + expected from Object.equals(Object) when the compared template sources came from the same + TemplateLoader instance. Also, it must not influence the equality if the source is open or + closed (TemplateLoader.closeTemplateSource(Object)).
    +
    Throws:
    +
    IOException - When an error occurs that makes it impossible to find out if the template exists, or to access the + existing template. Don't throw exception if the template doesn't exist, instead return with + null then!
    +
    +
  + + + +
  - +
    getLastModified
    +
```
public long getLastModified(Object templateSource)
```
    +
    Description copied from interface: TemplateLoader
    +
    Returns the time of last modification of the specified template source. This method is called after + findTemplateSource().
    +
    +
    Specified by:
    +
    getLastModified in interface TemplateLoader
    +
    Parameters:
    +
    templateSource - an object representing a template source, obtained through a prior call to + TemplateLoader.findTemplateSource(String). This must be an object on which + TemplateLoader.closeTemplateSource(Object) wasn't applied yet.
    +
    Returns:
    +
    the time of last modification of the specified template source, or -1 if the time is not known.
    +
    +
  + + + +
  - +
    getReader
    +
```
public Reader getReader(Object templateSource,
+                        String encoding)
+                 throws IOException
```
    +
    Description copied from interface: TemplateLoader
    +
    Returns the character stream of a template represented by the specified template source. This method is possibly + called for multiple times for the same template source object, and it must always return a Reader that + reads the template from its beginning. Before this method is called for the second time (or later), its caller + must close the previously returned Reader, and it must not use it anymore. That is, this method is not + required to support multiple concurrent readers for the same source templateSource object. + +
    + Typically, this method is called if the template is missing from the cache, or if after calling + TemplateLoader.findTemplateSource(String) and TemplateLoader.getLastModified(Object) it was determined that the cached copy + of the template is stale. Then, if it turns out that the encoding parameter used doesn't match the actual + template content (based on the #ftl encoding=... header), this method will be called for a second time + with the correct encoding parameter value.
    +
    +
    Specified by:
    +
    getReader in interface TemplateLoader
    +
    Parameters:
    +
    templateSource - an object representing a template source, obtained through a prior call to + TemplateLoader.findTemplateSource(String). This must be an object on which + TemplateLoader.closeTemplateSource(Object) wasn't applied yet.
    +
    encoding - the character encoding used to translate source bytes to characters. Some loaders may not have access + to the byte representation of the template stream, and instead directly obtain a character stream. + These loaders should ignore the encoding parameter.
    +
    Returns:
    +
    A Reader representing the template character stream. It's the responsibility of the caller (which + is TemplateCache usually) to close() it. The Reader is not required to work after + the templateSource was closed (TemplateLoader.closeTemplateSource(Object)).
    +
    Throws:
    +
    IOException - if an I/O error occurs while accessing the stream.
    +
    +
  + + + +
  - +
    closeTemplateSource
    +
```
public void closeTemplateSource(Object templateSource)
+                         throws IOException
```
    +
    Description copied from interface: TemplateLoader
    +
    Closes the template source, releasing any resources held that are only required for reading the template and/or + its metadata. This is the last method that is called by the TemplateCache for a template source, except + that Object.equals(Object) is might called later too. TemplateCache ensures that this method will + be called on every object that is returned from TemplateLoader.findTemplateSource(String).
    +
    +
    Specified by:
    +
    closeTemplateSource in interface TemplateLoader
    +
    Parameters:
    +
    templateSource - the template source that should be closed.
    +
    Throws:
    +
    IOException
    +
    +
  + + + +
  - +
    getURLConnectionUsesCaches
    +
```
public Boolean getURLConnectionUsesCaches()
```
    +
    Getter pair of setURLConnectionUsesCaches(Boolean).
    +
    +
    Since:
    +
    2.3.21
    +
    +
  + + + +
  - +
    setURLConnectionUsesCaches
    +
```
public void setURLConnectionUsesCaches(Boolean urlConnectionUsesCaches)
```
    +
    It does the same as URLTemplateLoader.setURLConnectionUsesCaches(Boolean); see there.
    +
    +
    Since:
    +
    2.3.21
    +
    +
  + + + +
  - +
    toString
    +
```
public String toString()
```
    +
    Show class name and some details that are useful in template-not-found errors.
    +
    +
    Overrides:
    +
    toString in class Object
    +
    Since:
    +
    2.3.21
    +
    +
  + + + +
  - +
    getAttemptFileAccess
    +
```
public boolean getAttemptFileAccess()
```
    +
    Getter pair of setAttemptFileAccess(boolean).
    +
    +
    Since:
    +
    2.3.23
    +
    +
  + + + +
  - +
    setAttemptFileAccess
    +
```
public void setAttemptFileAccess(boolean attemptLoadingFromFile)
```
    +
    Specifies that before loading templates with ServletContext.getResource(String), it should try to load + the template as File; default is true, though it's not always recommended anymore. This is a + workaround for the case when the servlet container doesn't show template modifications after the template was + already loaded earlier. But it's certainly better to counter this problem by disabling the URL connection cache + with setURLConnectionUsesCaches(Boolean), which is also the default behavior with + incompatible_improvements 2.3.21 + and later.
    +
    +
    Since:
    +
    2.3.23
    +
    +
  +
+

+ + + + + + + + + + + + + + + + +

Packages that use CacheStorage
Package	Description
freemarker.cache	+ Template loading and caching. +
freemarker.template	+ The fundamental, most commonly used API-s of FreeMarker; +start with `Configuration` (see also the +Getting Stared in the Manual.) +

+ + +

Uses of CacheStorage in freemarker.cache

+ + + + + + + + + + + + + + + + +

Subinterfaces of CacheStorage in freemarker.cache
Modifier and Type	Interface and Description
`interface`	`CacheStorageWithGetSize` + A cache storage that has a `getSize()` method for returning the current number of cache entries. +
`interface`	`ConcurrentCacheStorage` + An optional interface for cache storage that knows whether it can be + concurrently accessible without synchronization. +

+ + + + + + + + + + + + + + + + + + + + + + + + +

Classes in freemarker.cache that implement CacheStorage
Modifier and Type	Class and Description
`class`	`MruCacheStorage` + A cache storage that implements a two-level Most Recently Used cache. +
`class`	`NullCacheStorage` + A cache storage that doesn't store anything. +
`class`	`SoftCacheStorage` + Soft cache storage is a cache storage that uses `SoftReference` + objects to hold the objects it was passed, therefore allows the garbage + collector to purge the cache when it determines that it wants to free up + memory. +
`class`	`StrongCacheStorage` + Strong cache storage is a cache storage that simply wraps a `Map`. +

+ + + + + + + + + + + + +

Methods in freemarker.cache that return CacheStorage
Modifier and Type	Method and Description
`CacheStorage`	TemplateCache.`getCacheStorage()`

+ + + + + + + + + + + + + + + + +

Constructors in freemarker.cache with parameters of type CacheStorage
Constructor and Description
`TemplateCache(TemplateLoader templateLoader, + CacheStorage cacheStorage)` + Deprecated. + Use `TemplateCache.TemplateCache(TemplateLoader, CacheStorage, Configuration)` instead. + +
`TemplateCache(TemplateLoader templateLoader, + CacheStorage cacheStorage, + Configuration config)` + Same as + `TemplateCache.TemplateCache(TemplateLoader, CacheStorage, TemplateLookupStrategy, TemplateNameFormat, Configuration)` + with `TemplateLookupStrategy.DEFAULT_2_3_0` and `TemplateNameFormat.DEFAULT_2_3_0`. +
`TemplateCache(TemplateLoader templateLoader, + CacheStorage cacheStorage, + TemplateLookupStrategy templateLookupStrategy, + TemplateNameFormat templateNameFormat, + Configuration config)`

+ + +

Uses of CacheStorage in freemarker.template

+ + + + + + + + + + + + +

Methods in freemarker.template that return CacheStorage
Modifier and Type	Method and Description
`CacheStorage`	Configuration.`getCacheStorage()` + The getter pair of `Configuration.setCacheStorage(CacheStorage)`. +

+ + + + + + + + + + + + +

Methods in freemarker.template with parameters of type CacheStorage
Modifier and Type	Method and Description
`void`	Configuration.`setCacheStorage(CacheStorage cacheStorage)` + Sets the `CacheStorage` used for caching `Template`-s; + the earlier content of the template cache will be dropt. +

Class WebappTemplateLoader

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WebappTemplateLoader

WebappTemplateLoader

Method Detail

findTemplateSource

getLastModified

getReader

closeTemplateSource

getURLConnectionUsesCaches

setURLConnectionUsesCaches

toString

getAttemptFileAccess

setAttemptFileAccess

Uses of Interface
freemarker.cache.CacheStorage

Uses of CacheStorage in freemarker.cache

Uses of CacheStorage in freemarker.template

Uses of Interface
freemarker.cache.CacheStorageWithGetSize

Uses of CacheStorageWithGetSize in freemarker.cache

Uses of Class
freemarker.cache.ClassTemplateLoader

Uses of Interface
freemarker.cache.ConcurrentCacheStorage

Uses of ConcurrentCacheStorage in freemarker.cache

Uses of Class
freemarker.cache.FileTemplateLoader

Uses of Class
freemarker.cache.MruCacheStorage

Class WebappTemplateLoader

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WebappTemplateLoader

WebappTemplateLoader

Method Detail

findTemplateSource

getLastModified

getReader

closeTemplateSource

getURLConnectionUsesCaches

setURLConnectionUsesCaches

toString

getAttemptFileAccess

setAttemptFileAccess

Uses of Interfacefreemarker.cache.CacheStorage

Uses of CacheStorage in freemarker.cache

Uses of CacheStorage in freemarker.template

Uses of Interfacefreemarker.cache.CacheStorageWithGetSize

Uses of CacheStorageWithGetSize in freemarker.cache

Uses of Classfreemarker.cache.ClassTemplateLoader

Uses of Interfacefreemarker.cache.ConcurrentCacheStorage

Uses of ConcurrentCacheStorage in freemarker.cache

Uses of Classfreemarker.cache.FileTemplateLoader

Uses of Classfreemarker.cache.MruCacheStorage

Uses of Interface
freemarker.cache.CacheStorage

Uses of Interface
freemarker.cache.CacheStorageWithGetSize

Uses of Class
freemarker.cache.ClassTemplateLoader

Uses of Interface
freemarker.cache.ConcurrentCacheStorage

Uses of Class
freemarker.cache.FileTemplateLoader

Uses of Class
freemarker.cache.MruCacheStorage