import com.sun.org.apache.xpath.internal.patterns.UnionPattern; //导入依赖的package包/类
/**
 * Compile an entire match pattern expression.
 *
 * @param opPos The current position in the m_opMap array.
 *
 * @return reference to {@link com.sun.org.apache.xpath.internal.patterns.UnionPattern} instance.
 *
 * @throws TransformerException if a error occurs creating the Expression.
 */
protected Expression matchPattern(int opPos) throws TransformerException
{
  locPathDepth++;
  try
  {
    // First, count...
    int nextOpPos = opPos;
    int i;

    for (i = 0; getOp(nextOpPos) == OpCodes.OP_LOCATIONPATHPATTERN; i++)
    {
      nextOpPos = getNextOpPos(nextOpPos);
    }

    if (i == 1)
      return compile(opPos);

    UnionPattern up = new UnionPattern();
    StepPattern[] patterns = new StepPattern[i];

    for (i = 0; getOp(opPos) == OpCodes.OP_LOCATIONPATHPATTERN; i++)
    {
      nextOpPos = getNextOpPos(opPos);
      patterns[i] = (StepPattern) compile(opPos);
      opPos = nextOpPos;
    }

    up.setPatterns(patterns);

    return up;
  }
  finally
  {
    locPathDepth--;
  }
}
 

import com.sun.org.apache.xpath.internal.patterns.UnionPattern; //导入依赖的package包/类
/**
 * Visit a union pattern.
 * @param owner The owner of the expression, to which the expression can
 *              be reset if rewriting takes place.
 * @param pattern The union pattern object.
 * @return true if the sub expressions should be traversed.
 */
public boolean visitUnionPattern(ExpressionOwner owner, UnionPattern pattern)
{
        return true;
}