1 // $Id: CQLBooleanNode.java,v 1.7 2002-11-06 00:05:58 mike Exp $
3 package org.z3950.zing.cql;
7 * Represents a boolean node in a CQL parse-tree.
9 * @version $Id: CQLBooleanNode.java,v 1.7 2002-11-06 00:05:58 mike Exp $
11 public abstract class CQLBooleanNode extends CQLNode {
12 CQLBooleanNode() {} // prevent javadoc from documenting this
15 * The root of a parse-tree representing the left-hand side.
20 * The root of a parse-tree representing the right-hand side.
26 public String toXCQL(int level) {
27 return (indent(level) + "<triple>\n" +
29 left.toXCQL(level+1) +
30 right.toXCQL(level+1) +
31 indent(level) + "</triple>\n");
34 // Represents the boolean operation itself: overridden for CQLProxNode
35 String booleanXQL(int level) {
36 return(indent(level) + "<boolean>\n" +
37 indent(level+1) + "<value>" + op() + "</value>\n" +
38 indent(level) + "</boolean>\n");
41 public String toCQL() {
42 // ### We don't always need parens around the operands
43 return "(" + left.toCQL() + ") " + op() + " (" + right.toCQL() + ")";