public class StringTemplateLoader extends java.lang.Object implements TemplateLoader
TemplateLoader that uses a Map with Strings as its source of
templates.
In most case the regular way of loading templates from files will be fine.
However, there can be situations where you don't want to or can't load a
template from a file, e.g. if you have to deploy a single jar for
JavaWebStart or if they are contained within a database.
A single template can be created manually
e.g.
String templateStr="Hello ${user}";
Template t = new Template("name", new StringReader(templateStr),
new Configuration());
If, however, you want to create templates from strings which import other
templates this method doesn't work.
In that case you can create a StringTemplateLoader and add each template to
it:
StringTemplateLoader stringLoader = new StringTemplateLoader();
stringLoader.putTemplate("greetTemplate", "<#macro greet>Hello");
stringLoader.putTemplate("myTemplate", "<#include \"greetTemplate\"><@greet/> World!");
Then you tell your Configuration object to use it:
cfg.setTemplateLoader(stringLoader);After that you should be able to use the templates as usual. Often you will want to combine a StringTemplateLoader with another loader. You can do so using a
MultiTemplateLoader.| Constructor and Description |
|---|
StringTemplateLoader() |
| Modifier and Type | Method and Description |
|---|---|
void |
closeTemplateSource(java.lang.Object templateSource)
Closes the template source.
|
java.lang.Object |
findTemplateSource(java.lang.String name)
Finds the object that acts as the source of the template with the
given name.
|
long |
getLastModified(java.lang.Object templateSource)
Returns the time of last modification of the specified template source.
|
java.io.Reader |
getReader(java.lang.Object templateSource,
java.lang.String encoding)
Returns the character stream of a template represented by the specified
template source.
|
void |
putTemplate(java.lang.String name,
java.lang.String templateSource)
Puts a template into the loader.
|
void |
putTemplate(java.lang.String name,
java.lang.String templateSource,
long lastModified)
Puts a template into the loader.
|
public void putTemplate(java.lang.String name,
java.lang.String templateSource)
putTemplate(String, String, long)
passing System.currentTimeMillis() as the third argument.name - the name of the template.templateSource - the source code of the template.public void putTemplate(java.lang.String name,
java.lang.String templateSource,
long lastModified)
name - the name of the template.templateSource - the source code of the template.lastModified - the time of last modification of the template in
terms of System.currentTimeMillis()public void closeTemplateSource(java.lang.Object templateSource)
TemplateLoaderTemplateCache for a template source. The framework guarantees that
this method will be called on every object that is returned from
TemplateLoader.findTemplateSource(String).closeTemplateSource in interface TemplateLoadertemplateSource - the template source that should be closed.public java.lang.Object findTemplateSource(java.lang.String name)
TemplateLoaderTemplateCache when a template
is requested, before calling either TemplateLoader.getLastModified(Object) or
TemplateLoader.getReader(Object, String).findTemplateSource in interface TemplateLoadername - 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.TemplateLoader.getLastModified(Object) and
TemplateLoader.getReader(Object, String). Null must be returned if the source
for the template can not be found (do not throw FileNotFoundException!).
The returned object may will be compared with a cached template source
object for equality, using the equals method. Thus,
objects returned for the same physical source must be equivalent
according to equals method, otherwise template caching
can become very ineffective!public long getLastModified(java.lang.Object templateSource)
TemplateLoaderfindTemplateSource().getLastModified in interface TemplateLoadertemplateSource - an object representing a template source, obtained
through a prior call to TemplateLoader.findTemplateSource(String).public java.io.Reader getReader(java.lang.Object templateSource,
java.lang.String encoding)
TemplateLoadergetLastModified()
if it's determined that a cached copy of the template is unavailable
or stale.getReader in interface TemplateLoadertemplateSource - an object representing a template source, obtained
through a prior call to TemplateLoader.findTemplateSource(String).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 will should ignore the encoding parameter.close().