java.lang.Object | +--java.security.Permission | +--java.io.FilePermission
Untamed: This class represents access to a file or directory. A FilePermission consists of a pathname and a set of actions valid for that pathname.
Pathname is the pathname of the file or directory granted the specified
actions. A pathname that ends in "/*" (where "/" is
the file separator character, File.separatorChar) indicates
all the files and directories contained in that directory. A pathname
that ends with "/-" indicates (recursively) all files
and subdirectories contained in that directory. A pathname consisting of
the special token "<<ALL FILES>>" matches any file.
Note: A pathname consisting of a single "*" indicates all the files in the current directory, while a pathname consisting of a single "-" indicates all the files in the current directory and (recursively) all files and subdirectories contained in the current directory.
The actions to be granted are passed to the constructor in a string containing a list of one or more comma-separated keywords. The possible keywords are "read", "write", "execute", and "delete". Their meaning is defined as follows:
Runtime.exec to
be called. Corresponds to SecurityManager.checkExec.
File.delete to
be called. Corresponds to SecurityManager.checkDelete.
The actions string is converted to lowercase before processing.
Be careful when granting FilePermissions. Think about the implications of granting read and especially write access to various files and directories. The "<<ALL FILES>>" permission with write action is especially dangerous. This grants permission to write to the entire file system. One thing this effectively allows is replacement of the system binary, including the JVM runtime environment.
Please note: Code can always read a file from the same directory it's in (or a subdirectory of that directory); it does not need explicit permission to do so.
java.security.Permission,
java.security.Permissions,
java.security.PermissionCollection(package private)
FilePermission(String path,
int mask)
FilePermission(String path,
String actions)
private static String
getActions(int mask)
boolean
implies(Permission p)
(package private) boolean
impliesIgnoreMask(FilePermission that)
PermissionCollection
newPermissionCollection()
private void
readObject(ObjectInputStream s)
private void
writeObject(ObjectOutputStream s)
private static final int EXECUTE
private static final int WRITE
private static final int READ
private static final int DELETE
private static final int ALL
private static final int NONE
private transient int mask
private transient boolean directory
private transient boolean recursive
private String actions
private transient String cpath
private static final String RECURSIVE
private static final String WILD
private static final String SEP_RECURSIVE
private static final String SEP_WILD
private static final long serialVersionUID
public FilePermission(String path, String actions)
A pathname that ends in "/*" (where "/" is
the file separator character, File.separatorChar) indicates
a directory and all the files contained in that directory. A pathname
that ends with "/-" indicates a directory and (recursively) all files
and subdirectories contained in that directory. The special pathname
"<<ALL FILES>>" matches all files.
A pathname consisting of a single "*" indicates all the files in the current directory, while a pathname consisting of a single "-" indicates all the files in the current directory and (recursively) all files and subdirectories contained in the current directory.
path - the pathname of the file/directory.actions - the action string.FilePermission(String path, int mask)
implies method.
path - the pathname of the file/directory.mask - the action mask to use.private void init(int mask)
mask - the actions mask to use.public boolean implies(Permission p)
More specifically, this method returns true if:
implies in class Permissionp - the permission to check against.
boolean impliesIgnoreMask(FilePermission that)
that - the FilePermission to check against.
public boolean equals(Object obj)
equals in class Permissionobj - the object we are testing for equality with this object.
public int hashCode()
hashCode in class Permissionprivate static int getMask(String actions)
int getMask()
private static String getActions(int mask)
public String getActions()
getActions
will return the string "read,write".
getActions in class Permissionpublic PermissionCollection newPermissionCollection()
FilePermission objects must be stored in a manner that allows them
to be inserted into the collection in any order, but that also enables the
PermissionCollection implies
method to be implemented in an efficient (and consistent) manner.
For example, if you have two FilePermissions:
"/tmp/-", "read"
"/tmp/scratch/foo", "write"
and you are calling the implies method with the FilePermission:
"/tmp/scratch/foo", "read,write",then the
implies function must
take into account both the "/tmp/-" and "/tmp/scratch/foo"
permissions, so the effective permission is "read,write",
and implies returns true. The "implies" semantics for
FilePermissions are handled properly by the PermissionCollection object
returned by this newPermissionCollection method.
newPermissionCollection in class Permissionprivate void writeObject(ObjectOutputStream s) throws IOException
private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException