import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
protected void calcFirstPos(CMStateSet toSet)
{
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE)
    {
        // Its the the union of the first positions of our children.
        toSet.setTo(fLeftChild.firstPos());
        toSet.union(fRightChild.firstPos());
    }
     else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ)
    {
        //
        //  If our left child is nullable, then its the union of our
        //  children's first positions. Else is our left child's first
        //  positions.
        //
        toSet.setTo(fLeftChild.firstPos());
        if (fLeftChild.isNullable())
            toSet.union(fRightChild.firstPos());
    }
     else
    {
        throw new RuntimeException("ImplementationMessages.VAL_BST");
    }
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
protected void calcLastPos(CMStateSet toSet)
{
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE)
    {
        // Its the the union of the first positions of our children.
        toSet.setTo(fLeftChild.lastPos());
        toSet.union(fRightChild.lastPos());
    }
     else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ)
    {
        //
        //  If our right child is nullable, then its the union of our
        //  children's last positions. Else is our right child's last
        //  positions.
        //
        toSet.setTo(fRightChild.lastPos());
        if (fRightChild.isNullable())
            toSet.union(fLeftChild.lastPos());
    }
     else
    {
        throw new RuntimeException("ImplementationMessages.VAL_BST");
    }
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
public CMBinOp(int type, CMNode leftNode, CMNode rightNode)
{
    super(type);

    // Insure that its one of the types we require
    if ((type() != XMLContentSpec.CONTENTSPECNODE_CHOICE)
    &&  (type() != XMLContentSpec.CONTENTSPECNODE_SEQ))
    {
        throw new RuntimeException("ImplementationMessages.VAL_BST");
    }

    // Store the nodes and init any data that needs it
    fLeftChild = leftNode;
    fRightChild = rightNode;
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
public boolean isNullable()
{
    //
    //  If its an alternation, then if either child is nullable then
    //  this node is nullable. If its a concatenation, then both of
    //  them have to be nullable.
    //
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE)
        return (fLeftChild.isNullable() || fRightChild.isNullable());
    else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ)
        return (fLeftChild.isNullable() && fRightChild.isNullable());
    else
        throw new RuntimeException("ImplementationMessages.VAL_BST");
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
/** Constructs a content model leaf. */
public CMLeaf(QName element, int position)  {
    super(XMLContentSpec.CONTENTSPECNODE_LEAF);

    // Store the element index and position
    fElement.setValues(element);
    fPosition = position;
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
public CMUniOp(int type, CMNode childNode)
{
    super(type);

    // Insure that its one of the types we require
    if ((type() != XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE)
    &&  (type() != XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE)
    &&  (type() != XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE))
    {
        throw new RuntimeException("ImplementationMessages.VAL_UST");
    }

    // Store the node and init any data that needs it
    fChild = childNode;
}
 

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec; //导入依赖的package包/类
public boolean isNullable()
{
    //
    //  For debugging purposes, make sure we got rid of all non '*'
    //  repetitions. Otherwise, '*' style nodes are always nullable.
    //
    if (type() == XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE)
        return fChild.isNullable();
    else
        return true;
}