public class URLFileSystemHelperDecorator extends URLFileSystemHelper
URLFileSystemHelperDecorator
class provides a base decorator
implementation for a URLFileSystemHelper
. This class allows a
URLFileSystemHelper
instance registered with URLFileSystem
to be supplemented with additional behavior.
By default, all URLFileSystemHelper
method calls are forwarded to
the delegate without interference.URLFileSystem
Modifier and Type | Field and Description |
---|---|
protected URLFileSystemHelper |
_helper |
Modifier | Constructor and Description |
---|---|
protected |
URLFileSystemHelperDecorator(URLFileSystemHelper helper)
Constructor.
|
Modifier and Type | Method and Description |
---|---|
void |
addURLFileSystemListener(java.net.URL rootURL,
URLFileSystemListener listener) |
boolean |
canCreate(java.net.URL url)
Tests whether the application can create the resource at the specified
URL . |
boolean |
canDelete(java.net.URL url)
Tests whether the application can delete the resource at the specified
URL . |
java.net.URL |
canonicalize(java.net.URL url)
Returns a canonical form of the
URL , if one is available. |
boolean |
canRead(java.net.URL url)
Tests whether the application can read the resource at the
specified
URL . |
boolean |
canWrite(java.net.URL url)
Tests whether the application can modify the resource at the
specified
URL . |
java.net.URL |
convertSuffix(java.net.URL url,
java.lang.String oldSuffix,
java.lang.String newSuffix)
Takes the given
URL and checks if its Object.toString()
representation ends with the specified oldSuffix . |
java.io.Reader |
createReader(java.net.URL url,
java.lang.String encoding)
Creates a
Reader on the specified URL with the
specified encoding. |
java.net.URL |
createTempFile(java.lang.String prefix,
java.lang.String suffix,
java.net.URL directory)
Creates a new empty temporary file in the specified directory using the
given prefix and suffix strings to generate its name.
|
void |
delete(java.net.URL url)
Deletes the content pointed to by the specified
URL . |
java.net.URL |
ensureSuffix(java.net.URL url,
java.lang.String suffix)
This method ensures that the specified
URL ends with the
specified suffix . |
boolean |
equals(java.net.URL url1,
java.net.URL url2)
Compares the specified
URL objects to determine whether
they point to the same resource. |
boolean |
exists(java.net.URL url)
Returns
true if the specified URL points to a
resource that currently exists; returns false
otherwise. |
java.net.URL |
getBaseParent(java.net.URL url,
java.lang.String relativeSpec)
This method gets the base directory fully containing the relative path.
|
javax.swing.Icon |
getDefaultIcon(java.net.URL url)
Returns one of the built-in
JFileChooser icons
for a directory or file, depending on the type of resource
represented by the URL . |
java.lang.String |
getFileName(java.net.URL url)
Returns the name of the file contained by the
URL , not
including any protocol, hostname authentication, directory path,
anchor, or query. |
URLFileSystemHelper |
getHelper()
Gets the delegate helper object for this decorator instance.
|
long |
getLength(java.net.URL url)
Returns the number of bytes contained in the resource that the
specified
URL points to. |
java.lang.String |
getName(java.net.URL url)
Returns the name of the file contained by the
URL , not
including any protocol, hostname authentication, directory path,
anchor, or query. |
java.net.URL |
getParent(java.net.URL url)
Returns the
URL representing the parent directory of
the specified URL . |
java.lang.String |
getPath(java.net.URL url)
Returns the path part of the
URL . |
java.lang.String |
getPathNoExt(java.net.URL url)
Returns the path part of the
URL without the last file
extension. |
java.lang.String |
getPlatformPathName(java.net.URL url)
Returns the platform-dependent String representation of the
URL ; the returned string should be considered acceptable
for users to read. |
java.lang.String |
getSuffix(java.net.URL url)
If a dot ('.') occurs in the path portion of the
URL , then
all of the text starting at the last dot is returned, including
the dot. |
java.lang.String |
getSystemDisplayName(java.net.URL url)
The default implementation maps to
URLFileSystem.getFileName(URL) . |
javax.swing.Icon |
getSystemIcon(java.net.URL url)
The default implementation returns the default icon obtained from
URLFileSystem.getDefaultIcon(URL) . |
int |
hashCode(java.net.URL url)
Computes a hash code for the specified
URL object consistent
with URLFileSystemHelper.equals(java.net.URL, java.net.URL) . |
boolean |
hasSuffix(java.net.URL url,
java.lang.String suffix)
Returns
true if the path part of the URL
ends with the given suffix String. |
void |
insertNextDecorator(URLFileSystemHelperDecorator decorator)
Inserts the specified decorator into the decorator linked list after
this decorator.
|
boolean |
isBaseURLFor(java.net.URL url1,
java.net.URL url2)
Returns
true if url1 represents a
a directory and url2 points to a location within
url1 's directory tree. |
boolean |
isDirectory(java.net.URL url)
Tests whether the location indicated by the
URL is
a directory. |
boolean |
isDirectoryPath(java.net.URL url)
Tests whether the location indicated by the
URL
represents a directory path. |
boolean |
isHidden(java.net.URL url)
Tests whether the resource indiciated by the
URL is a
hidden file. |
boolean |
isLocal(java.net.URL url)
Determines whether the
URL points to a resource on the local
machine, or whether it requires network access. |
boolean |
isReadOnly(java.net.URL url)
Returns
true if the resource is read-only. |
boolean |
isRegularFile(java.net.URL url)
Tests whether the resource indiciated by the
URL is
a regular file. |
boolean |
isValid(java.net.URL url)
Tests whether the specified
URL is valid. |
long |
lastModified(java.net.URL url)
Returns the last modification time (timestamp) of the resource
indicated by the specified
URL in milliseconds since
00:00:00 GMT, Jan 1, 1970. |
java.net.URL[] |
list(java.net.URL url)
Returns an array of
URL s naming files and directories in
the directory indicated by the URL . |
java.net.URL[] |
list(java.net.URL url,
URLFilter filter)
Returns an array of
URL s naming files and directories in
the directory indicated by the URL ; the specified
URLFilter is applied to determine which URL s will
be returned. |
URLFileSystem.FileInfo[] |
ls(java.net.URL url)
Returns an array of
URLFileSystem.FileInfo objects describing
files and directories in the directory indicated by the URL . |
URLFileSystem.FileInfo[] |
ls(java.net.URL url,
URLFilter filter)
Returns an array of
URLFileSystem.FileInfo objects describing
files and directories in the directory indicated by the URL
that satisfy the specified URLFilter . |
URLFileSystem.FileInfo[] |
lsCached(java.net.URL url) |
URLFileSystem.FileInfo[] |
lsCached(java.net.URL url,
URLFilter filter) |
boolean |
mkdir(java.net.URL url)
Creates the directory indicated by the
URL . |
boolean |
mkdirs(java.net.URL url)
Creates the directory indicated by the specified
URL
including any necessary but nonexistent parent directories. |
java.io.InputStream |
openInputStream(java.net.URL url)
Opens an
InputStream on the specified URL . |
java.io.OutputStream |
openOutputStream(java.net.URL url)
Opens an
OutputStream on the URL . |
void |
removeURLFileSystemListener(java.net.URL rootURL,
URLFileSystemListener listener) |
void |
rename(java.net.URL oldURL,
java.net.URL newURL)
Renames the resource indicated by the first
URL to the
name indicated by the second URL . |
boolean |
setLastModified(java.net.URL url,
long time)
Sets the last-modified timestamp of the resource indicated by
the
URL to the time specified by time . |
boolean |
setReadOnly(java.net.URL url,
boolean readOnly)
Sets the read-only status of the resource indicated by the
URL according to the specified readOnly
flag. |
java.lang.String |
toDisplayString(java.net.URL url)
Returns a displayable form of the complete
URL . |
java.lang.String |
toEncodedString(java.net.URL url) |
java.lang.String |
toRelativeSpec(java.net.URL url,
java.net.URL base)
This method attempts all possible ways of deriving a
relative URI reference as described in
RFC 2396
using the
url parameter as the URL
whose relative URI reference is to be determined and the
base parameter as the URL that serves as the
base document for the url pararmeter. |
java.lang.String |
toRelativeSpec(java.net.URL url,
java.net.URL base,
boolean mustConsumeBase)
Variant of
URLFileSystemHelper.toRelativeSpec(URL, URL) that has a flag
that indicates whether the base URL should be fully
consumed in the process of calculating the relative spec. |
appendRelativePath, areEqual, areEqualPathElems, code, getPort, getTempDirectory, haveSameAuthority, haveSameHost, haveSamePath, haveSamePort, haveSameProtocol, haveSameQuery, haveSameRef, haveSameUserInfo, list, listRoots, toEncodedString, verifyList
protected URLFileSystemHelper _helper
protected URLFileSystemHelperDecorator(URLFileSystemHelper helper)
helper
- the delegate helper object.public URLFileSystemHelper getHelper()
public void insertNextDecorator(URLFileSystemHelperDecorator decorator)
decorator
- The decorator to insertjava.lang.IllegalStateException
- if this method is called when this
decorator has a null helper.public java.net.URL canonicalize(java.net.URL url)
URLFileSystemHelper
URL
, if one is available.
The default implementation just returns the specified URL
as-is.
canonicalize
in class URLFileSystemHelper
public boolean canRead(java.net.URL url)
URLFileSystemHelper
URL
.canRead
in class URLFileSystemHelper
true
if and only if the specified
URL
points to a resource that exists and can be
read by the application; false
otherwise.public boolean canWrite(java.net.URL url)
URLFileSystemHelper
URL
.canWrite
in class URLFileSystemHelper
true
if and only if the specified
URL
points to a file that exists and the
application is allowed to write to the file; false
otherwise.public boolean canCreate(java.net.URL url)
URLFileSystemHelper
URL
.canCreate
in class URLFileSystemHelper
true
if the resource at the specified URL
exists or can be created; false
otherwise.public boolean canDelete(java.net.URL url)
URLFileSystemHelper
URL
.canDelete
in class URLFileSystemHelper
true
if the resource at the specified URL
can be deleted.URLFileSystem.canDelete(URL)
public boolean isValid(java.net.URL url)
URLFileSystemHelper
URL
is valid. If the resource
pointed by the URL
exists the method returns true
.
If the resource does not exist, the method tests that all components
of the path can be created.isValid
in class URLFileSystemHelper
true
if the URL
is valid.public java.net.URL convertSuffix(java.net.URL url, java.lang.String oldSuffix, java.lang.String newSuffix)
URLFileSystemHelper
URL
and checks if its Object.toString()
representation ends with the specified oldSuffix
. If
it does, the suffix is replaced with newSuffix
. Both
suffix parameters must include the leading dot ('.') if the dot is
part of the suffix. If the specified URL
does not end
with the oldSuffix
, then the newSuffix
is simply appended to the end of the original URL
.convertSuffix
in class URLFileSystemHelper
public void delete(java.net.URL url) throws java.io.IOException
URLFileSystemHelper
URL
. If
the content is a file (or analogous to a file), then the file is
removed from its directory (or container). If the content is a
directory (or analogous to a directory), then the directory is
removed only if it is empty (i.e. contains no other files or
directories).The default implementation does nothing.
delete
in class URLFileSystemHelper
java.io.IOException
- if an I/O exception occurred when trying
to delete the URL.public java.net.URL ensureSuffix(java.net.URL url, java.lang.String suffix)
URLFileSystemHelper
URL
ends with the
specified suffix
. The suffix does not necessarily
have to start with a ".", so if a leading "." is required, the
specified suffix must contain it -- e.g. ".java", ".class".
If the URL
already ends in the specified suffix, then
the URL
itself is returned. Otherwise, a new
URL
is created with the the specified suffix appended
to the original URL
's path part, and the new URL
is returned.
The default implementation first checks with URLFileSystemHelper.hasSuffix(URL, String)
to see if the URL
already ends
with the specified suffix. If not, the suffix is simply appended
to the path part of the URL
, and the new URL
is
returned.
ensureSuffix
in class URLFileSystemHelper
URL
, based on the specified URL
, whose
path part ends with the specified suffix.public boolean equals(java.net.URL url1, java.net.URL url2)
URLFileSystemHelper
URL
objects to determine whether
they point to the same resource. This method returns
true
if the URL
s point to the same resource
and returns false
if the URL
s do not point
to the same resource.
This method and all subclass implementations can assume that both
URL
parameters are not null
. The
URLFileSystem.equals(URL, URL)
method is responsible for
checking that the two URL
s are not null
.
It can also be assumed that both URL
parameters have
the same protocol and that the protocol is appropriate for this
URLFileSystemHelper
. This determination is also
the responsibility of URLFileSystem.equals(URL, URL)
.
The default implementation for this method checks to see if
the various parts of the URLs are equal. Unlike URL.equals(java.lang.Object)
,
the host names are not resolved to InetAddresses.
equals
in class URLFileSystemHelper
public int hashCode(java.net.URL url)
URLFileSystemHelper
URL
object consistent
with URLFileSystemHelper.equals(java.net.URL, java.net.URL)
.
This method and all subclass implementations can assume that the
URL
parameter is not null
. The
URLFileSystem.hashCode(URL)
method is responsible for
ensuring this condition.
It can also be assumed that the protocol is appropriate for this
URLFileSystemHelper
. The URLFileSystem.hashCode(URL)
method is also responsible for ensuring this condition and for
incorporating the protocol into the hash code.
The default implementation for this method computes the hash code from
the hash codes of the various parts of the URLs are equal. Unlike
URL.equals(java.lang.Object)
, the host names is not resolved to an InetAddress.
hashCode
in class URLFileSystemHelper
public boolean exists(java.net.URL url)
URLFileSystemHelper
true
if the specified URL
points to a
resource that currently exists; returns false
otherwise.
The default implementation simply returns false
without doing anything.
exists
in class URLFileSystemHelper
public javax.swing.Icon getDefaultIcon(java.net.URL url)
URLFileSystemHelper
JFileChooser
icons
for a directory or file, depending on the type of resource
represented by the URL
.getDefaultIcon
in class URLFileSystemHelper
URLFileSystemHelper.getSystemIcon(URL)
public java.lang.String getFileName(java.net.URL url)
URLFileSystemHelper
URL
, not
including any protocol, hostname authentication, directory path,
anchor, or query. This simply returns the simple filename. For
example, if you pass in an URL
whose string representation
is:
protocol://host:1010/dir1/dir2/file.ext#anchor?query
the returned value is "file.ext
" (without the
quotes).
The returned file name should only be used for display purposes
and not for opening streams or otherwise trying to locate the
resource indicated by the URL
.
getFileName
in class URLFileSystemHelper
public long getLength(java.net.URL url)
URLFileSystemHelper
URL
points to. If the length cannot be
determined, -1
is returned.
The default implementation attempts to get the content length from
the URLConnection
associated with the URL
. If that
fails for some reason (e.g. the resource does not exist, there was
some other an I/O exception, etc.), -1
is returned.
getLength
in class URLFileSystemHelper
URLConnection
public java.lang.String getName(java.net.URL url)
URLFileSystemHelper
URL
, not
including any protocol, hostname authentication, directory path,
anchor, or query. This simply returns the simple filename. For
example, if you pass in an URL
whose string representation
is:
protocol://host:1010/dir1/dir2/file.ext1.ext2#anchor?query
the returned value is "file.ext1
" (without the quotes).
The returned file name should only be used for display purposes
and not for opening streams or otherwise trying to locate the
resource indicated by the URL
.
The default implementation first calls URLFileSystemHelper.getFileName(URL)
to
get the file name part. Then all characters starting with the
last occurrence of '.' are removed. The remaining string is then
returned.
Note: The implementation of this method changed in the 11.1.1 release of the platform to trim the filename on the last '.'. In previous releases of the platform, it would trim the filename on the first '.'.
getName
in class URLFileSystemHelper
public java.net.URL getParent(java.net.URL url)
URLFileSystemHelper
URL
representing the parent directory of
the specified URL
. If there is no parent directory,
then null
is returned.
The default implementation returns the value of invoking
URLFactory.newURL( url, ".." )
, removing the reference
portion of the URL.
getParent
in class URLFileSystemHelper
public java.lang.String getPath(java.net.URL url)
URLFileSystemHelper
URL
. The returned string
is acceptable to use in one of the URLFactory
methods
that takes a path.
The default implementation delegates to URL.getPath()
.
getPath
in class URLFileSystemHelper
public java.lang.String getPathNoExt(java.net.URL url)
URLFileSystemHelper
URL
without the last file
extension. To clarify, the following examples demonstrate the
different cases that come up:
URL |
String |
/dir/file.ext |
/dir/file |
/dir/file.ext1.ext2 |
/dir/file.ext1 |
/dir1.ext1/dir2.ext2/file.ext1.ext2 |
/dir1.ext1/dir2.ext2/file.ext1 |
/file.ext |
/file |
/dir.ext/file |
/dir.ext/file |
/dir/file |
/dir/file |
/file |
/file |
/.ext |
/ |
URLFileSystemHelper.getPath(URL)
and then trims off all of the characters beginning
with the last "." in the path, if and only if the last "." comes
after the last "/" in the path. If the last "." comes before
the last "/" or if there is no "." at all, then the entire path
is returned.getPathNoExt
in class URLFileSystemHelper
public java.lang.String getPlatformPathName(java.net.URL url)
URLFileSystemHelper
URL
; the returned string should be considered acceptable
for users to read. In general, the returned string should omit
as many parts of the URL
as possible. For the "file"
protocol, therefore, the platform pathname should just be the
pathname alone (no protocol) using the appropriate file separator
character for the current platform. For other protocols, it may
be necessary to reformat the URL
string into a more
human-readable form. That decision is left to each
URLFileSystemHelper
implementor.
The default implementation returns url.toString()
.
If the URL
is null
, the empty string is
returned.getPlatformPathName
in class URLFileSystemHelper
URL
in
platform-dependent notation. This value should only be used for
display purposes and not for opening streams or otherwise trying
to locate the document.public java.lang.String getSuffix(java.net.URL url)
URLFileSystemHelper
URL
, then
all of the text starting at the last dot is returned, including
the dot. If the last dot is also the last character in the path,
then the dot by itself is returned. If there is no dot in the
path, then the empty string is returned.getSuffix
in class URLFileSystemHelper
public java.lang.String getSystemDisplayName(java.net.URL url)
URLFileSystemHelper
URLFileSystem.getFileName(URL)
.getSystemDisplayName
in class URLFileSystemHelper
public javax.swing.Icon getSystemIcon(java.net.URL url)
URLFileSystemHelper
URLFileSystem.getDefaultIcon(URL)
.getSystemIcon
in class URLFileSystemHelper
URLFileSystemHelper.getDefaultIcon(URL)
public boolean hasSuffix(java.net.URL url, java.lang.String suffix)
URLFileSystemHelper
true
if the path part of the URL
ends with the given suffix
String. The suffix can
be any String and doesn't necessarily have to be one that begins
with a dot ('.'). If you are trying to test whether the path
part of the URL
ends with a particular file extension,
then the suffix
parameter should begin with a '.'
character to ensure that you get the right return value.hasSuffix
in class URLFileSystemHelper
public boolean isBaseURLFor(java.net.URL url1, java.net.URL url2)
URLFileSystemHelper
true
if url1
represents a
a directory and url2
points to a location within
url1
's directory tree.isBaseURLFor
in class URLFileSystemHelper
public boolean isDirectory(java.net.URL url)
URLFileSystemHelper
URL
is
a directory.
The default implementation always returns false
.
isDirectory
in class URLFileSystemHelper
true
if and only if the location indicated
by the URL
exists and is a directory;
false
otherwise.public boolean isDirectoryPath(java.net.URL url)
URLFileSystemHelper
URL
represents a directory path. The directory path specified by
the URL
need not exist.
This method is intended to be a higher performance version of
the URLFileSystemHelper.isDirectory(URL)
method. Implementations of this
method should attempt to ascertain whether the specified URL
represents a directory path by simply examining the URL
itself. Time consuming i/o operations should be
avoided.
The default implementation returns true
if the path
part of the URL
ends with a '/' and the query and ref
parts of the URL
are null.
isDirectoryPath
in class URLFileSystemHelper
true
if the location indicated by the
URL
represents a directory path; the directory path need
not exist.public boolean isHidden(java.net.URL url)
URLFileSystemHelper
URL
is a
hidden file. The exact definition of hidden is
protocol-dependent and possibly system-dependent. On UNIX
systems, a file is considered to be hidden if its name begins
with a period character ('.'). On Win32 systems, a file is
considered to be hidden if it has been marked as such in the
file system.
The default implementation always returns false
.
isHidden
in class URLFileSystemHelper
public boolean isReadOnly(java.net.URL url)
URLFileSystemHelper
true
if the resource is read-only. A return
value of false
means that trying to get an
OutputStream
or trying to write to an OutputStream
based on the URL
will cause an exception to be thrown.
The default implementation always returns true
. This
means that all resources are considered read-only unless a
protocol-specific URLFileSystemHelper
is registered for the
specified URL
and is able to determine that the resource
underlying the specified URL
is not read-only.
isReadOnly
in class URLFileSystemHelper
public boolean isRegularFile(java.net.URL url)
URLFileSystemHelper
URL
is
a regular file. A regular is a file that is not a
directory and, in addition, satisfies other system-dependent
criteria.
The default implementation returns the value of
exists( url ) && !isDirectory( url )
.
isRegularFile
in class URLFileSystemHelper
true
if and only if the resource
indicated by the URL
exists and is a normal
file.public boolean isLocal(java.net.URL url)
URLFileSystemHelper
URL
points to a resource on the local
machine, or whether it requires network access.isLocal
in class URLFileSystemHelper
url
- the URLtrue
if the URL
is local, false
if it requires network accesspublic long lastModified(java.net.URL url)
URLFileSystemHelper
URL
in milliseconds since
00:00:00 GMT, Jan 1, 1970. If the timestamp can't be determined,
-1
is returned.
The default implementation attemps to get the last modified time
from the URLConnection
associated with the URL
. If
that fails for some reason (e.g. the resource does not exist, there
was some other I/O exception, etc.), -1
is returned.
lastModified
in class URLFileSystemHelper
URLConnection
public java.net.URL[] list(java.net.URL url)
URLFileSystemHelper
URL
s naming files and directories in
the directory indicated by the URL
. If the specified
URL
does not represent a directory, then this method
returns null
. Otherwise, an array of URL
s
is returned, one for each file or directory in the directory.
URL
s representing the directory itself or its parent are
not included in the result. There is no guarantee that the
URL
s will occur in any particular order.
The default implementation always returns an empty URL
array.
list
in class URLFileSystemHelper
URL
s naming the files and directories
in the directory indicated by the URL
. The array will
be empty if the directory is empty. Returns null
if the URL
does not represent a directory or if an
I/O error occurs.public java.net.URL[] list(java.net.URL url, URLFilter filter)
URLFileSystemHelper
URL
s naming files and directories in
the directory indicated by the URL
; the specified
URLFilter
is applied to determine which URL
s will
be returned. If the specified URL
does not represent a
directory, then this method returns null
.
Otherwise, an array of URL
s is returned, one for each file
or directory in the directory that is accepted by the specified
filter. URL
s representing the directory itself or its
parent are not included in the result. There is no guarantee that
the URL
s will occur in any particular order.
The default implementation calls URLFileSystemHelper.list(URL)
first and
then applies the URLFilter
to the resulting list.
list
in class URLFileSystemHelper
URL
s naming the files and directories
in the directory indicated by the URL
that are accepted
by the specified URLFilter
. The array will be empty if
the directory is empty. Returns null
if the
URL
does not represent a directory or if an I/O error
occurs.public URLFileSystem.FileInfo[] ls(java.net.URL url)
URLFileSystemHelper
URLFileSystem.FileInfo
objects describing
files and directories in the directory indicated by the URL
.
If the specified URL
does not represent a directory, then
this method returns null
. Otherwise, an array of
URLFileSystem.FileInfo
objects is returned, one for each
file or directory in the directory.
URLFilesystem.FileInfo
objects representing the
directory itself or its parent are not included in the result.
There is no guarantee that the URLFileSystem.FileInfo
objects will be returned in any specific order; in particular, they
are not guaranteed to be returned in alphabetical order.
The default implementation calls ls(URL,
null)
.
ls
in class URLFileSystemHelper
URLFileSystem.FileInfo
objects
describing the files and directories in the directory indicated by
the URL
. The array will be empty if the directory is
empty. Returns null
if the URL
does not
represent a directory or if an I/O error occurs.public URLFileSystem.FileInfo[] ls(java.net.URL url, URLFilter filter)
URLFileSystemHelper
URLFileSystem.FileInfo
objects describing
files and directories in the directory indicated by the URL
that satisfy the specified URLFilter
.
The behavior of this method is the same as URLFileSystemHelper.ls(URL)
, except
that the URL
s indicated by the returned array must
satisfy the filter. If the given filter is null
, then
all URL
s are accepted. Otherwise, an URL
satisfies the filter if and only if the value of true
results when the URLFilter.accept(URL)
method of the filter
is invoked on the URL
of a file or directory in the
directory that it denotes.
The default implementation calls URLFileSystem.list(URL,
URLFilter)
and builds the URLFileSystem.FileInfo
objects from the returned URL
s.
ls
in class URLFileSystemHelper
URLFileSystem.FileInfo
objects
describing the files and directories in the directory indicated by
the URL
. The array will be empty if the directory is
empty. Returns null
if the URL
does not
represent a directory or if an I/O error occurs.public URLFileSystem.FileInfo[] lsCached(java.net.URL url)
lsCached
in class URLFileSystemHelper
public URLFileSystem.FileInfo[] lsCached(java.net.URL url, URLFilter filter)
lsCached
in class URLFileSystemHelper
public boolean mkdir(java.net.URL url)
URLFileSystemHelper
URL
.
The default implementation always returns false
.
mkdir
in class URLFileSystemHelper
true
if and only if the directory was
created; false
otherwise.public boolean mkdirs(java.net.URL url)
URLFileSystemHelper
URL
including any necessary but nonexistent parent directories. Note
that if this operation fails, it may have succeeded in creating
some of the necessary parent directories. This method returns
true
if the directory was created along with all
necessary parent directories or if the directories already
exist; it returns false
otherwise.mkdirs
in class URLFileSystemHelper
true
if all directories were created
successfully or exist; false
if there was a
failure somewhere.
Note that even if false
is returned, some directories
may still have been created.public java.net.URL createTempFile(java.lang.String prefix, java.lang.String suffix, java.net.URL directory) throws java.io.IOException
URLFileSystemHelper
createTempFile
in class URLFileSystemHelper
prefix
- The prefix string to be used in generating the file's
name; must be at least three characters longsuffix
- The suffix string to be used in generating the file's
name; may be null
, in which case the
suffix ".tmp"
will be useddirectory
- The directory in which the file is to be created, or
null
if the default temporary-file
directory is to be usedURL
of the newly-created empty file.java.io.IOException
- if a file could not be createdpublic java.io.InputStream openInputStream(java.net.URL url) throws java.io.IOException
URLFileSystemHelper
InputStream
on the specified URL
.
The default implementation attempts to open the InputStream
through the URLConnection
associated with the URL
.
If the URLConnection
implementation does not support an
InputStream
then an UnknownServiceException
(a runtime exception) will be thrown.
openInputStream
in class URLFileSystemHelper
java.io.FileNotFoundException
- if the resource at the
specified URL does not exist.java.io.IOException
- if an I/O error occurs when trying to open
the InputStream
.java.net.UnknownServiceException
- if the
URLConnection
backing the specified URL
does not
support an InputStream
.IOException
,
URLConnection
,
UnknownServiceException
public java.io.OutputStream openOutputStream(java.net.URL url) throws java.io.IOException
URLFileSystemHelper
OutputStream
on the URL
. If the file
does not exist, the file should be created. If the directory
path to the file does not exist, all necessary directories
should be created.
The default implementation attempts to open the
OutputStream
through the URLConnection
associated
with the URL
. If the URLConnection
implementation
does not support an OutputStream
then an
UnknownServiceException
(a runtime exception) will
be thrown.
openOutputStream
in class URLFileSystemHelper
java.io.IOException
- if an I/O error occurs when trying to open
the OutputStream
.java.net.UnknownServiceException
- if the
URLConnection
backing the specified URL
does not
support an OutputStream
.IOException
,
URLConnection
,
UnknownServiceException
public void rename(java.net.URL oldURL, java.net.URL newURL) throws java.io.IOException
URLFileSystemHelper
URL
to the
name indicated by the second URL
.The default implementation does nothing.
rename
in class URLFileSystemHelper
java.io.IOException
- if an I/O exception occurs while renaming
the URL.URLFileSystem.renameTo(URL, URL)
,
URLFileSystem.renameEx(URL, URL)
public boolean setLastModified(java.net.URL url, long time)
URLFileSystemHelper
URL
to the time specified by time
.
The time is specified in the number of milliseconds since
the epoch (00:00:00 GMT Jan 1, 1970). The return value
indicates whether or not the setting of the timestamp
succeeded.
The default implementation always returns false
without doing anything.
setLastModified
in class URLFileSystemHelper
public boolean setReadOnly(java.net.URL url, boolean readOnly)
URLFileSystemHelper
URL
according to the specified readOnly
flag. The return value indicates whether or not the setting
of the read-only flag succeeded.
The default implementation always returns false
without doing anything.
setReadOnly
in class URLFileSystemHelper
public java.lang.String toDisplayString(java.net.URL url)
URLFileSystemHelper
URL
.
The default implementation delegates to URL.toString()
.
toDisplayString
in class URLFileSystemHelper
public java.lang.String toEncodedString(java.net.URL url)
toEncodedString
in class URLFileSystemHelper
public java.lang.String toRelativeSpec(java.net.URL url, java.net.URL base)
URLFileSystemHelper
url
parameter as the URL
whose relative URI reference is to be determined and the
base
parameter as the URL
that serves as the
base document for the url
pararmeter. If it is not
possible to produce a relative URI reference because the two
URL
s are too different, then a full, absolute
reference for the url
parameter is returned.
Whatever value is returned by this method, it can be used in
conjunction with the base
URL
to
reconstruct the fully-qualified URL
by using one of the
URL
constructors that takes a context URL
plus
a String
spec (i.e. the String
returned by this
method).
Both the url
and base
parameters should
point to documents and be absolute URL
s. Specifically,
the base
parameter does not need to be modified to
represent the base directory if the base
parameter
already points to a document that is in the directory to which
the url
parameter will be made relative. This
relationship between url
and base
is
exactly how relative references are treated within HTML documents.
Relative references in an HTML page are resolved against the HTML
page's base URL. The base URL is the HTML page itself, not the
directory that contains it.
If either the url
or base
parameter
needs to represent a directory rather than a file, they must end
with a "/" in the path part of the URL
, such as:
http://host.com/root/my_directory/
The algorithm used by this method to determine the relative reference closely follows the recommendations made in RFC 2396. The following steps are performed, in order, to determine the relative reference:
File
so that, for example,
on Win32 the comparison is case-insensitive,
whereas on Unix the comparison is
case-sensitive. When the protocol is not
"file", comparison is always case-sensitive. (This
distinction is made by FileURLFileSystemHelper
,
which overrides the relevant part of the algorithm.)
URL
(except for the document name itself),
then a "../" sequence is prepended to the resulting
relative path for each base path element that was not
consumed while matching path elements.
url
were consumed, then those path elements are appended
to the resulting relative path as well. If the first
remaining path element in url
contains
a ':' character and there is no "../" sequence was
prepended to the relative reference, then a "./"
sequence is prepended to prevent the ':' character
from being interpreted as a protocol delimiter (this
is a special case in RFC
2396).
url
are not appended.This method is implemented using the template method design pattern, so it is possible for subclasses to override just part of the algorithm in order to handle protocol-specific details.
toRelativeSpec
in class URLFileSystemHelper
public java.lang.String toRelativeSpec(java.net.URL url, java.net.URL base, boolean mustConsumeBase)
URLFileSystemHelper
URLFileSystemHelper.toRelativeSpec(URL, URL)
that has a flag
that indicates whether the base URL
should be fully
consumed in the process of calculating the relative spec.
If mustConsumeBase
is true
, then
this method will return a non-null
relative
spec if and only if the base URL
was fully consumed
in the process of calculating the relative spec. Otherwise,
if any part of the base URL
remained, then this
method returns null
.
If mustConsumeBase
is false
, then
this method will return a non-null
relative
spec regardless of how much of the base URL
is
consumed during the determination.
toRelativeSpec
in class URLFileSystemHelper
public java.net.URL getBaseParent(java.net.URL url, java.lang.String relativeSpec)
URLFileSystemHelper
url
should be absolute and point to a directory.
It must end with a "/" in the path part of the URL
, such as:
http://host.com/root/my_directory/
If the url
does not end with a "/", it will be assumed
that the url
points to a document. The document name will
then be stripped in order to determine the parent directory.
The relativeSpec
parameter should be a relative path.
If the relativeSpec
does not end with a "/", it will be
assumed that the relativeSpec
points to a document.
The document name will then be stripped in order to determine the
parent directory.
For example, if the url
points to:
file://c:/root/dir1/dir2/dir3/
and the relativeSpec
is:
dir2/dir3
The returned value would be:
file://c:/root/dir1/
If the relativeSpec
path elements are not fully
contained in the last part of the url
path the
value returned is the url itself if the url path ends with a
"/" or the url parent otherwise.getBaseParent
in class URLFileSystemHelper
public java.io.Reader createReader(java.net.URL url, java.lang.String encoding) throws java.io.IOException
URLFileSystemHelper
Reader
on the specified URL
with the
specified encoding.
The default implementation opens the InputStream
and
then creates an InputStreamReader
.
createReader
in class URLFileSystemHelper
java.io.IOException
- if an I/O error occurs when trying to open
the InputStream
.java.net.UnknownServiceException
- if the
URLConnection
backing the specified URL
does not
support an InputStream
.InputStreamReader
,
IOException
,
URLConnection
,
UnknownServiceException
public void addURLFileSystemListener(java.net.URL rootURL, URLFileSystemListener listener)
addURLFileSystemListener
in class URLFileSystemHelper
public void removeURLFileSystemListener(java.net.URL rootURL, URLFileSystemListener listener)
removeURLFileSystemListener
in class URLFileSystemHelper