/*
* Copyright (c) OSGi Alliance (2004, 2016). 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.condpermadmin;
import java.util.ArrayList;
import java.util.List;
Condition representation used by the Conditional Permission Admin service.
This class encapsulates two pieces of information: a Condition type (class name), which must implement Condition, and the arguments passed to its constructor.
In order for a Condition represented by a ConditionInfo to be instantiated and considered during a permission check, its Condition class must be available from the system classpath.
The Condition class must either:
- Declare a public static
getCondition method that takes a Bundle object and a ConditionInfo object as arguments. That method must return an object that implements the Condition interface.
- Implement the
Condition interface and define a public constructor that takes a Bundle object and a ConditionInfo object as arguments.
Author: $Id: f96821be9ea49552285ed5eb699b05371f7f9ba8 $ @Immutable
/**
* Condition representation used by the Conditional Permission Admin service.
*
* <p>
* This class encapsulates two pieces of information: a Condition <i>type</i>
* (class name), which must implement {@code Condition}, and the arguments
* passed to its constructor.
*
* <p>
* In order for a Condition represented by a {@code ConditionInfo} to be
* instantiated and considered during a permission check, its Condition class
* must be available from the system classpath.
*
* <p>
* The Condition class must either:
* <ul>
* <li>Declare a public static {@code getCondition} method that takes a
* {@code Bundle} object and a {@code ConditionInfo} object as arguments. That
* method must return an object that implements the {@code Condition} interface.
* </li>
* <li>Implement the {@code Condition} interface and define a public constructor
* that takes a {@code Bundle} object and a {@code ConditionInfo} object as
* arguments.</li>
* </ul>
*
* @Immutable
* @author $Id: f96821be9ea49552285ed5eb699b05371f7f9ba8 $
*/
public class ConditionInfo {
private final String type;
private final String[] args;
Constructs a ConditionInfo from the specified type and args. Params: - type – The fully qualified class name of the Condition represented by this
ConditionInfo. - args – The arguments for the Condition. These arguments are available to the newly created Condition by calling the
getArgs() method.
Throws: - NullPointerException – If
type is null.
/**
* Constructs a {@code ConditionInfo} from the specified type and args.
*
* @param type The fully qualified class name of the Condition represented
* by this {@code ConditionInfo}.
* @param args The arguments for the Condition. These arguments are
* available to the newly created Condition by calling the
* {@link #getArgs()} method.
* @throws NullPointerException If {@code type} is {@code null}.
*/
public ConditionInfo(String type, String[] args) {
this.type = type;
this.args = (args != null) ? args.clone() : new String[0];
if (type == null) {
throw new NullPointerException("type is null");
}
}
Constructs a ConditionInfo object from the specified encoded ConditionInfo string. White space in the encoded ConditionInfo string is ignored. Params: - encodedCondition – The encoded
ConditionInfo.
Throws: - IllegalArgumentException – If the specified
encodedCondition is not properly formatted.
See Also:
/**
* Constructs a {@code ConditionInfo} object from the specified encoded
* {@code ConditionInfo} string. White space in the encoded
* {@code ConditionInfo} string is ignored.
*
* @param encodedCondition The encoded {@code ConditionInfo}.
* @see #getEncoded()
* @throws IllegalArgumentException If the specified
* {@code encodedCondition} is not properly formatted.
*/
public ConditionInfo(String encodedCondition) {
if (encodedCondition == null) {
throw new NullPointerException("missing encoded condition");
}
if (encodedCondition.length() == 0) {
throw new IllegalArgumentException("empty encoded condition");
}
try {
char[] encoded = encodedCondition.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 bracket");
}
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 args which are quoted and encoded */
List<String> argsList = new ArrayList<String>();
while (encoded[pos] == '"') {
pos++;
begin = pos;
while (encoded[pos] != '"') {
if (encoded[pos] == '\\') {
pos++;
}
pos++;
}
argsList.add(unescapeString(encoded, begin, pos));
pos++;
if (Character.isWhitespace(encoded[pos])) {
/* skip whitespace */
while (Character.isWhitespace(encoded[pos])) {
pos++;
}
}
}
this.args = argsList.toArray(new String[0]);
/* 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 bracket");
}
} catch (ArrayIndexOutOfBoundsException e) {
throw new IllegalArgumentException("parsing terminated abruptly");
}
}
Returns the string encoding of this ConditionInfo in a form suitable for restoring this ConditionInfo.
The encoded format is:
[type "arg0" "arg1" ...]
where argN are strings that must be encoded for proper parsing. Specifically, the ", \, carriage return, and line feed characters must be 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 "arg0"
and between the arguments.
Returns: The string encoding of this ConditionInfo.
/**
* Returns the string encoding of this {@code ConditionInfo} in a form
* suitable for restoring this {@code ConditionInfo}.
*
* <p>
* The encoded format is:
*
* <pre>
* [type "arg0" "arg1" ...]
* </pre>
*
* where <i>argN</i> are strings that must be encoded for proper parsing.
* Specifically, the {@code "}, {@code \}, carriage return, and line feed
* characters must be escaped using {@code \"}, {@code \\}, {@code \r}, and
* {@code \n}, respectively.
*
* <p>
* The encoded string contains no leading or trailing whitespace characters.
* A single space character is used between type and "<i>arg0</i>"
* and between the arguments.
*
* @return The string encoding of this {@code ConditionInfo}.
*/
public final String getEncoded() {
StringBuilder output = new StringBuilder();
output.append('[');
output.append(type);
for (int i = 0; i < args.length; i++) {
output.append(" \"");
escapeString(args[i], output);
output.append('\"');
}
output.append(']');
return output.toString();
}
Returns the string representation of this ConditionInfo. The string is created by calling the getEncoded method on this ConditionInfo. Returns: The string representation of this ConditionInfo.
/**
* Returns the string representation of this {@code ConditionInfo}. The
* string is created by calling the {@code getEncoded} method on this
* {@code ConditionInfo}.
*
* @return The string representation of this {@code ConditionInfo}.
*/
@Override
public String toString() {
return getEncoded();
}
Returns the fully qualified class name of the condition represented by this ConditionInfo. Returns: The fully qualified class name of the condition represented by this ConditionInfo.
/**
* Returns the fully qualified class name of the condition represented by
* this {@code ConditionInfo}.
*
* @return The fully qualified class name of the condition represented by
* this {@code ConditionInfo}.
*/
public final String getType() {
return type;
}
Returns arguments of this ConditionInfo. Returns: The arguments of this ConditionInfo. An empty array is returned if the ConditionInfo has no arguments.
/**
* Returns arguments of this {@code ConditionInfo}.
*
* @return The arguments of this {@code ConditionInfo}. An empty array is
* returned if the {@code ConditionInfo} has no arguments.
*/
public final String[] getArgs() {
return args.clone();
}
Determines the equality of two ConditionInfo objects. This method checks that specified object has the same type and args as this ConditionInfo object. Params: - obj – The object to test for equality with this
ConditionInfo object.
Returns: true if obj is a ConditionInfo, and has the same type and args as this ConditionInfo object; false otherwise.
/**
* Determines the equality of two {@code ConditionInfo} objects.
*
* This method checks that specified object has the same type and args as
* this {@code ConditionInfo} object.
*
* @param obj The object to test for equality with this
* {@code ConditionInfo} object.
* @return {@code true} if {@code obj} is a {@code ConditionInfo}, and has
* the same type and args as this {@code ConditionInfo} object;
* {@code false} otherwise.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof ConditionInfo)) {
return false;
}
ConditionInfo other = (ConditionInfo) obj;
if (!type.equals(other.type) || args.length != other.args.length)
return false;
for (int i = 0; i < args.length; i++) {
if (!args[i].equals(other.args[i]))
return false;
}
return true;
}
Returns the hash code value for this object.
Returns: A hash code value for this object.
/**
* Returns the hash code value for this object.
*
* @return A hash code value for this object.
*/
@Override
public int hashCode() {
int h = 31 * 17 + type.hashCode();
for (int i = 0; i < args.length; i++) {
h = 31 * h + args[i].hashCode();
}
return h;
}
This escapes the quotes, backslashes, \n, and \r in the string using a
backslash and appends the newly escaped string to a StringBuilder.
/**
* This escapes the quotes, backslashes, \n, and \r in the string using a
* backslash and appends the newly escaped string to a StringBuilder.
*/
private static void escapeString(String str, StringBuilder 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.
/**
* Takes an encoded character array and decodes it into a new String.
*/
private static String unescapeString(char[] str, int begin, int end) {
StringBuilder output = new StringBuilder(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();
}
}