/*
* JBoss, the OpenSource J2EE webOS
*
* Distributable under LGPL license.
* See terms of license at gnu.org.
*/
package javax.management;
import gnu.regexp.UncheckedRE;
/**
* A Match Query Expression.<p>
*
* Returns true when an attribute value matches the string expression.
*
* <p><b>Revisions:</b>
* <p><b>20020314 Adrian Brock:</b>
* <ul>
* <li>Fixed most of the escaping
* </ul>
* <p><b>20020317 Adrian Brock:</b>
* <ul>
* <li>Make queries thread safe
* </ul>
*
* @author <a href="mailto:Adrian.Brock@HappeningTimes.com">Adrian Brock</a>.
* @version $Revision: 1.5 $
*/
/*package*/ class MatchQueryExp
extends QueryExpSupport
{
// Constants ---------------------------------------------------
// Attributes --------------------------------------------------
/**
* The attribute to test
*/
AttributeValueExp attr;
/**
* The string to test
*/
StringValueExp string;
/**
* Regular Expression
*/
UncheckedRE re;
// Static ------------------------------------------------------
// Constructors ------------------------------------------------
/**
* Construct a new MATCH query expression
*
* @param attr the attribute to test
* @param string the string to test
*/
public MatchQueryExp(AttributeValueExp attr, StringValueExp string)
{
this.attr = attr;
this.string = string;
// Translate the pattern to a regexp
StringBuffer buffer = new StringBuffer();
char[] chars = string.toString().toCharArray();
boolean escaping = false;
for (int i=0; i < chars.length; i++)
{
// Turn on escaping
if (chars[i] == '\\' && escaping == false)
escaping = true;
else
{
// Match any character
if (chars[i] == '?' && escaping == false)
buffer.append("(?:.)");
// A literal question mark
else if (chars[i] == '?')
buffer.append("\\?");
// Match any number of characters including none
else if (chars[i] == '*' && escaping == false)
buffer.append("(?:.)*");
// A literal asterisk
else if (chars[i] == '*')
buffer.append("\\*");
// The hat character is literal
else if (chars[i] == '^')
buffer.append("\\^");
// The dollar sign is literal
else if (chars[i] == '$')
buffer.append("\\$");
// The back slash character is literal (avoids escaping)
else if (chars[i] == '\\')
buffer.append("\\\\");
// The dot character is literal
else if (chars[i] == '.')
buffer.append("\\.");
// The vertical line character is literal
else if (chars[i] == '|')
buffer.append("\\|");
// Escaping the open bracket
else if (chars[i] == '[' && escaping == true)
buffer.append("\\[");
// REVIEW: There are other more complicated expressions to escape
else
buffer.append(chars[i]);
escaping = false;
}
}
// REVIEW: Should this be an error?
if (escaping)
buffer.append("\\\\");
re = new UncheckedRE(buffer);
}
// Public ------------------------------------------------------
// QueryExp implementation -------------------------------------
public boolean apply(ObjectName name)
throws BadStringOperationException,
BadBinaryOpValueExpException,
BadAttributeValueExpException,
InvalidApplicationException
{
ValueExp calcAttr = attr.apply(name);
if (calcAttr instanceof StringValueExp)
{
return re.isMatch(((StringValueExp)calcAttr).toString());
}
// Correct?
return false;
}
// Object overrides --------------------------------------------
public String toString()
{
return new String("(" + attr.toString() + " matches " +
string.toString() + ")");
}
// Protected ---------------------------------------------------
// Private -----------------------------------------------------
// Inner classes -----------------------------------------------
}