org.osgi.service.permissionadmin.PermissionInfo Maven / Gradle / Ivy
/*
* $Header: /cvshome/build/org.osgi.service.permissionadmin/src/org/osgi/service/permissionadmin/PermissionInfo.java,v 1.16 2006/06/16 16:31:44 hargrave Exp $
*
* Copyright (c) OSGi Alliance (2001, 2006). All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.osgi.service.permissionadmin;
/**
* Permission representation used by the Permission Admin service.
*
*
* This class encapsulates three pieces of information: a Permission type
* (class name), which must be a subclass of
* java.security.Permission, and the name and actions
* arguments passed to its constructor.
*
*
* In order for a permission represented by a PermissionInfo to be
* instantiated and considered during a permission check, its Permission class
* must be available from the system classpath or an exported package. This
* means that the instantiation of a permission represented by a
* PermissionInfo may be delayed until the package containing its
* Permission class has been exported by a bundle.
*
* @version $Revision: 1.16 $
*/
public class PermissionInfo {
private String type;
private String name;
private String actions;
/**
* Constructs a PermissionInfo from the specified type, name, and
* actions.
*
* @param type The fully qualified class name of the permission represented
* by this PermissionInfo. The class must be a subclass
* of java.security.Permission and must define a
* 2-argument constructor that takes a name string and an
* actions string.
*
* @param name The permission name that will be passed as the first argument
* to the constructor of the Permission class identified
* by type.
*
* @param actions The permission actions that will be passed as the second
* argument to the constructor of the Permission class
* identified by type.
*
* @throws java.lang.NullPointerException if type is
* null.
* @throws java.lang.IllegalArgumentException if action is not
* null and name is null.
*/
public PermissionInfo(String type, String name, String actions) {
this.type = type;
this.name = name;
this.actions = actions;
if (type == null) {
throw new NullPointerException("type is null");
}
if ((name == null) && (actions != null)) {
throw new IllegalArgumentException("name missing");
}
}
/**
* Constructs a PermissionInfo object from the specified encoded
* PermissionInfo string. White space in the encoded
* PermissionInfo string is ignored.
*
*
* @param encodedPermission The encoded PermissionInfo.
* @see #getEncoded
* @throws java.lang.IllegalArgumentException If the
* encodedPermission is not properly formatted.
*/
public PermissionInfo(String encodedPermission) {
if (encodedPermission == null) {
throw new NullPointerException("missing encoded permission");
}
if (encodedPermission.length() == 0) {
throw new IllegalArgumentException("empty encoded permission");
}
try {
char[] encoded = encodedPermission.toCharArray();
int length = encoded.length;
int pos = 0;
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
/* the first character must be '(' */
if (encoded[pos] != '(') {
throw new IllegalArgumentException(
"expecting open parenthesis");
}
pos++;
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
/* type is not quoted or encoded */
int begin = pos;
while (!Character.isWhitespace(encoded[pos]) && (encoded[pos] != ')')) {
pos++;
}
if (pos == begin || encoded[begin] == '"') {
throw new IllegalArgumentException("expecting type");
}
this.type = new String(encoded, begin, pos - begin);
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
/* type may be followed by name which is quoted and encoded */
if (encoded[pos] == '"') {
pos++;
begin = pos;
while (encoded[pos] != '"') {
if (encoded[pos] == '\\') {
pos++;
}
pos++;
}
this.name = unescapeString(encoded, begin, pos);
pos++;
if (Character.isWhitespace(encoded[pos])) {
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
/* name may be followed by actions which is quoted and encoded */
if (encoded[pos] == '"') {
pos++;
begin = pos;
while (encoded[pos] != '"') {
if (encoded[pos] == '\\') {
pos++;
}
pos++;
}
this.actions = unescapeString(encoded, begin, pos);
pos++;
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
}
}
}
/* the final character must be ')' */
char c = encoded[pos];
pos++;
while ((pos < length) && Character.isWhitespace(encoded[pos])) {
pos++;
}
if ((c != ')') || (pos != length)) {
throw new IllegalArgumentException("expecting close parenthesis");
}
}
catch (ArrayIndexOutOfBoundsException e) {
throw new IllegalArgumentException("parsing terminated abruptly");
}
}
/**
* Returns the string encoding of this PermissionInfo in a form
* suitable for restoring this PermissionInfo.
*
*
* The encoded format is:
*
*
* (type)
*
*
* or
*
*
* (type "name")
*
*
* or
*
*
* (type "name" "actions")
*
*
* where name and actions are strings that are encoded for
* proper parsing. Specifically, the ",\, carriage
* return, and linefeed characters are escaped using \",
* \\,\r, and \n, respectively.
*
*
* The encoded string contains no leading or trailing whitespace
* characters. A single space character is used between type and
* "name" and between "name" and "actions".
*
* @return The string encoding of this PermissionInfo.
*/
public final String getEncoded() {
StringBuffer output = new StringBuffer(
8
+ type.length()
+ ((((name == null) ? 0 : name.length()) + ((actions == null) ? 0
: actions.length())) << 1));
output.append('(');
output.append(type);
if (name != null) {
output.append(" \"");
escapeString(name, output);
if (actions != null) {
output.append("\" \"");
escapeString(actions, output);
}
output.append('\"');
}
output.append(')');
return output.toString();
}
/**
* Returns the string representation of this PermissionInfo. The
* string is created by calling the getEncoded method on this
* PermissionInfo.
*
* @return The string representation of this PermissionInfo.
*/
public String toString() {
return getEncoded();
}
/**
* Returns the fully qualified class name of the permission represented by
* this PermissionInfo.
*
* @return The fully qualified class name of the permission represented by
* this PermissionInfo.
*/
public final String getType() {
return type;
}
/**
* Returns the name of the permission represented by this
* PermissionInfo.
*
* @return The name of the permission represented by this
* PermissionInfo, or null if the permission
* does not have a name.
*/
public final String getName() {
return name;
}
/**
* Returns the actions of the permission represented by this
* PermissionInfo.
*
* @return The actions of the permission represented by this
* PermissionInfo, or null if the permission
* does not have any actions associated with it.
*/
public final String getActions() {
return actions;
}
/**
* Determines the equality of two PermissionInfo objects.
*
* This method checks that specified object has the same type, name and
* actions as this PermissionInfo object.
*
* @param obj The object to test for equality with this
* PermissionInfo object.
* @return true if obj is a PermissionInfo,
* and has the same type, name and actions as this
* PermissionInfo object; false otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof PermissionInfo)) {
return false;
}
PermissionInfo other = (PermissionInfo) obj;
if (!type.equals(other.type) || ((name == null) ^ (other.name == null))
|| ((actions == null) ^ (other.actions == null))) {
return false;
}
if (name != null) {
if (actions != null) {
return name.equals(other.name) && actions
.equals(other.actions);
}
else {
return name.equals(other.name);
}
}
else {
return true;
}
}
/**
* Returns the hash code value for this object.
*
* @return A hash code value for this object.
*/
public int hashCode() {
int hash = type.hashCode();
if (name != null) {
hash ^= name.hashCode();
if (actions != null) {
hash ^= actions.hashCode();
}
}
return hash;
}
/**
* This escapes the quotes, backslashes, \n, and \r in the string using a
* backslash and appends the newly escaped string to a StringBuffer.
*/
private static void escapeString(String str, StringBuffer output) {
int len = str.length();
for (int i = 0; i < len; i++) {
char c = str.charAt(i);
switch (c) {
case '"' :
case '\\' :
output.append('\\');
output.append(c);
break;
case '\r' :
output.append("\\r");
break;
case '\n' :
output.append("\\n");
break;
default :
output.append(c);
break;
}
}
}
/**
* Takes an encoded character array and decodes it into a new String.
*/
private static String unescapeString(char[] str, int begin, int end) {
StringBuffer output = new StringBuffer(end - begin);
for (int i = begin; i < end; i++) {
char c = str[i];
if (c == '\\') {
i++;
if (i < end) {
c = str[i];
switch (c) {
case '"' :
case '\\' :
break;
case 'r' :
c = '\r';
break;
case 'n' :
c = '\n';
break;
default :
c = '\\';
i--;
break;
}
}
}
output.append(c);
}
return output.toString();
}
}