public class FileTemplateLoader extends java.lang.Object implements TemplateLoader
TemplateLoader
that uses files inside a specified directory as the source of templates. By default it does
security checks on the canonical path that will prevent it serving templates outside that specified
directory. If you want symbolic links that point outside the template directory to work, you need to disable this
feature by using FileTemplateLoader(File, boolean)
with true
second argument, but before that, check
the security implications there!Modifier and Type | Field and Description |
---|---|
java.io.File |
baseDir |
static java.lang.String |
SYSTEM_PROPERTY_NAME_EMULATE_CASE_SENSITIVE_FILE_SYSTEM
By setting this Java system property to
true , you can change the default of
#getEmulateCaseSensitiveFileSystem() . |
Constructor and Description |
---|
FileTemplateLoader()
Deprecated.
Relying on what the current directory is is a bad practice; use
FileTemplateLoader(File) instead. |
FileTemplateLoader(java.io.File baseDir)
Creates a new file template loader that will use the specified directory
as the base directory for loading templates.
|
FileTemplateLoader(java.io.File baseDir,
boolean disableCanonicalPathCheck)
Creates a new file template loader that will use the specified directory as the base directory for loading
templates.
|
Modifier and Type | Method and Description |
---|---|
void |
closeTemplateSource(java.lang.Object templateSource)
Closes the template source, releasing any resources held that are only required for reading the template and/or
its metadata.
|
java.lang.Object |
findTemplateSource(java.lang.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.
|
java.io.File |
getBaseDirectory()
Returns the base directory in which the templates are searched.
|
boolean |
getEmulateCaseSensitiveFileSystem()
Getter pair of
setEmulateCaseSensitiveFileSystem(boolean) . |
protected boolean |
getEmulateCaseSensitiveFileSystemDefault()
Returns the default of
getEmulateCaseSensitiveFileSystem() . |
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 |
setEmulateCaseSensitiveFileSystem(boolean nameCaseChecked)
Intended for development only, checks if the template name matches the case (upper VS lower case letters) of the
actual file name, and if it doesn't, it emulates a file-not-found even if the file system is case insensitive.
|
java.lang.String |
toString()
Show class name and some details that are useful in template-not-found errors.
|
public static java.lang.String SYSTEM_PROPERTY_NAME_EMULATE_CASE_SENSITIVE_FILE_SYSTEM
true
, you can change the default of
#getEmulateCaseSensitiveFileSystem()
.public final java.io.File baseDir
@Deprecated public FileTemplateLoader() throws java.io.IOException
FileTemplateLoader(File)
instead.user.dir
as the base directory for loading templates. It will not allow access to template files
that are accessible through symlinks that point outside the base directory.java.io.IOException
public FileTemplateLoader(java.io.File baseDir) throws java.io.IOException
baseDir
- the base directory for loading templatesjava.io.IOException
public FileTemplateLoader(java.io.File baseDir, boolean disableCanonicalPathCheck) throws java.io.IOException
baseDir
- the base directory for loading templatesdisableCanonicalPathCheck
- If true
, it will not check if the file to be loaded is inside the baseDir
or not,
according the canonical paths of the baseDir
and the file to load. Note that
Configuration.getTemplate(String)
and (its overloads) already prevents backing out from the
template directory with paths like /../../../etc/password
, however, that can be circumvented
with symbolic links or other file system features. If you really want to use symbolic links that point
outside the baseDir
, set this parameter to true
, but then be very careful with
template paths that are supplied by the visitor or an external system.java.io.IOException
public java.lang.Object findTemplateSource(java.lang.String name) throws java.io.IOException
TemplateLoader
findTemplateSource
in interface TemplateLoader
name
- The name (template root directory relative path) 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, by throwing an
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)
, 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)
).java.io.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!public long getLastModified(java.lang.Object templateSource)
TemplateLoader
findTemplateSource()
.getLastModified
in interface TemplateLoader
templateSource
- an object representing a template source (the template file), obtained through a prior call to
TemplateLoader.findTemplateSource(String)
. This must be an object on which
TemplateLoader.closeTemplateSource(Object)
wasn't applied yet.Long.MIN_VALUE
is reserved for internal use.public java.io.Reader getReader(java.lang.Object templateSource, java.lang.String encoding) throws java.io.IOException
TemplateLoader
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.
Unlike TemplateLoader.findTemplateSource(String)
, this method must not tolerate if the template is not found, and
must throw IOException
in that case.
getReader
in interface TemplateLoader
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.Reader
representing the template character stream; not null
. 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)
).java.io.IOException
- if an I/O error occurs while accessing the stream.public void closeTemplateSource(java.lang.Object templateSource)
TemplateLoader
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)
.closeTemplateSource
in interface TemplateLoader
templateSource
- the template source that should be closed.public java.io.File getBaseDirectory()
public void setEmulateCaseSensitiveFileSystem(boolean nameCaseChecked)
getBaseDirectory()
directory, must be listed. Positive results (matching case) will be cached without
expiration time.
The default in FileTemplateLoader
is false
, but subclasses may change they by overriding
getEmulateCaseSensitiveFileSystemDefault()
.
public boolean getEmulateCaseSensitiveFileSystem()
setEmulateCaseSensitiveFileSystem(boolean)
.protected boolean getEmulateCaseSensitiveFileSystemDefault()
getEmulateCaseSensitiveFileSystem()
. In FileTemplateLoader
it's
false
, unless the SYSTEM_PROPERTY_NAME_EMULATE_CASE_SENSITIVE_FILE_SYSTEM
system property was
set to true
, but this can be overridden here in custom subclasses. For example, if your environment
defines something like developer mode, you may want to override this to return true
on Windows.public java.lang.String toString()
toString
in class java.lang.Object