public final class FilePermission extends Permission implements Serializable
Pathname is the pathname of the file or directory granted the specified
actions. A pathname that ends in "/*" (where "/" is
the file separator character,
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", "delete", and "readlink". Their meaning is defined as follows:
Runtime.execto be called. Corresponds to
File.deleteto be called. Corresponds to
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.
|Constructor and Description|
Creates a new FilePermission object with the specified actions.
|Modifier and Type||Method and Description|
Checks two FilePermission objects for equality.
Returns the "canonical string representation" of the actions.
Returns the hash code value for this object.
Checks if this FilePermission object "implies" the specified permission.
Returns a new PermissionCollection object for storing FilePermission objects.
checkGuard, getName, toString
public FilePermission(String path, String actions)
A pathname that ends in "/*" (where "/" is
the file separator character,
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. The special pathname
"<<ALL FILES>>" matches any file.
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.
A pathname containing an empty string represents an empty path.
path- the pathname of the file/directory.
actions- the action string.
IllegalArgumentException- If actions is
null, empty or contains an action other than the specified possible actions.
public boolean implies(Permission p)
More specifically, this method returns true if:
p- the permission to check against.
trueif the specified permission is not
nulland is implied by this object,
public boolean equals(Object obj)
obj- the object we are testing for equality with this object.
trueif obj is a FilePermission, and has the same pathname and actions as this FilePermission object,
public int hashCode()
public String getActions()
getActionswill return the string "read,write".
public 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
method to be implemented in an efficient (and consistent) manner.
For example, if you have two FilePermissions:
and you are calling the
implies method with the FilePermission:
"/tmp/scratch/foo", "read,write",then the
impliesfunction must take into account both the "/tmp/-" and "/tmp/scratch/foo" permissions, so the effective permission is "read,write", and
impliesreturns true. The "implies" semantics for FilePermissions are handled properly by the PermissionCollection object returned by this
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2020, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.