javax.slee.profile.query.LongestPrefixMatch Maven / Gradle / Ivy

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package javax.slee.profile.query;

/**
 * The LongestPrefixMatch class represents a dynamic query expression that
 * determines if a profile attribute value is the longest prefix match against a
 * specified value.
 * 
 * This query expression can only be used with profile attributes of type
 * java.lang.String.
 * 

 * As an example of how this query expression can be used, consider a profile
 * specification that contains a String attribute named "prefix".
 * A number of profiles exist in a profile table as shown below:
 * 

 * 
 *   
 *   
 *   
 *   
 *   
 *   
 * Profile name Value of prefix attribute
A 1
B 12
C 123
D 1234
E 124
 * 

 * The table below indicates which profiles would match using the longest prefix rule
 * given various attribute values to test:
 * 

 * 
 *   
 *   
 *   
 *   
 *   
 *   
 *   
 * Test value Matching profile name
1653333 A
1256999 B
1238764 C
1234567 D
1247123 E
2987654 none
 */
public final class LongestPrefixMatch extends SimpleQueryExpression {
    /**
     * Create a LongestPrefixMatch query expression.  A profile will match
     * the expression criteria if the value of the attrName attribute
     * is the longest prefix match for the value specified by attrValue,
     * as determined by {@link String#startsWith(String)}.
     * @param attrName the name of the profile attribute to compare.
     * @param attrValue the value of the attribute to compare with.
     * @throws NullPointerException if either argument is null.
     */
    public LongestPrefixMatch(String attrName, String attrValue) {
        super(attrName, attrValue, null);
    }

    /**
     * Create a LongestPrefixMatch query expression.  A profile will match
     * the expression criteria if the value of the attrName attribute
     * is the longest prefix match for the value specified by attrValue,
     * as determined by {@link java.text.Collator#equals(String, String)}, where the
     * collator is obtained from the specified QueryCollator.
     * @param attrName the name of the profile attribute to compare.
     * @param attrValue the value of the attribute to compare with.
     * @param collator the collator to use for the comparison.  May be null.
     * @throws NullPointerException if either attrName or
     *        attrValue is null.
     */
    public LongestPrefixMatch(String attrName, String attrValue, QueryCollator collator) {
        super(attrName, attrValue, collator);
    }


    // protected

    // javadoc copied from parent
    protected String getRelation() {
        return "is-longest-prefix-of";
    }
}