1. /*
  2. * Copyright 2002-2004 The Apache Software Foundation
  3. *
  4. * Licensed under the Apache License, Version 2.0 (the "License");
  5. * you may not use this file except in compliance with the License.
  6. * You may obtain a copy of the License at
  7. *
  8. * http://www.apache.org/licenses/LICENSE-2.0
  9. *
  10. * Unless required by applicable law or agreed to in writing, software
  11. * distributed under the License is distributed on an "AS IS" BASIS,
  12. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13. * See the License for the specific language governing permissions and
  14. * limitations under the License.
  15. */
  16. package org.apache.commons.jxpath.ri.compiler;
  17. import org.apache.commons.jxpath.ri.EvalContext;
  18. import org.apache.commons.jxpath.ri.axes.UnionContext;
  19. /**
  20. * Implementation of Expression for the operation "|".
  21. *
  22. * @author Dmitri Plotnikov
  23. * @version $Revision: 1.3 $ $Date: 2004/02/29 14:17:39 $
  24. */
  25. public class CoreOperationUnion extends CoreOperation {
  26. public CoreOperationUnion(Expression args[]) {
  27. super(args);
  28. }
  29. public Object computeValue(EvalContext context) {
  30. EvalContext argCtxs[] = new EvalContext[args.length];
  31. for (int i = 0; i < args.length; i++) {
  32. Object value = args[i].compute(context);
  33. if (value instanceof EvalContext) {
  34. argCtxs[i] = (EvalContext) value;
  35. }
  36. else {
  37. argCtxs[i] = context.getRootContext().getConstantContext(value);
  38. }
  39. }
  40. return new UnionContext(context.getRootContext(), argCtxs);
  41. }
  42. protected int getPrecedence() {
  43. return 7;
  44. }
  45. protected boolean isSymmetric() {
  46. return true;
  47. }
  48. public String getSymbol() {
  49. return "|";
  50. }
  51. }