带有VTD XML解析器的XPath联合运算符

Question

有人能举一个例子，说明在VTD XML解析器中使用联合运算符（|）吗？以下内容不适用于VTD XML解析器，但适用于jxpath解析器/a |/b

Answer 1

好的，这是一个联合表达式的快速示例。

import com.ximpleware.AutoPilot;
import com.ximpleware.NavException;
import com.ximpleware.VTDException;
import com.ximpleware.VTDGen;
import com.ximpleware.VTDNav;


/**
 * An issue that seems to exist in VTD-XML 2.12 and 2.13 (but not 2.11) that causes lookups for default namespace nodes
 * to also pickup non-default namespaced nodes.
 */
public class VtdAutoPilotXpathIssueTest {

  private static final String XML = "<a xmlns:x=\"" + "urn:test" + "\"><b id=\"1\"/><x:b id=\"2\"/><b id=\"3\"/></a>";
  public static void main(String[] s) throws VTDException{
      VTDGen vg = new VTDGen();
      vg.setDoc(XML.getBytes());
      vg.parse(false);
      VTDNav vn = vg.getNav();
      AutoPilot ap = new AutoPilot(vn);
      ap.declareXPathNameSpace("abc", "urn:test");
      ap.selectXPath("//b|/a");
      int i=0;
      while((i=ap.evalXPath())!=-1){
          System.out.println(" token "+ vn.toRawString(i));
      }
  }
}