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package com.sun.org.apache.xpath.internal.axes;

import com.sun.org.apache.xml.internal.dtm.DTM;
import com.sun.org.apache.xml.internal.dtm.DTMFilter;
import com.sun.org.apache.xml.internal.dtm.DTMIterator;
import com.sun.org.apache.xml.internal.utils.PrefixResolver;
import com.sun.org.apache.xpath.internal.compiler.Compiler;
import com.sun.org.apache.xpath.internal.compiler.OpMap;

Base for iterators that handle predicates. Does the basic next node logic, so all the derived iterator has to do is get the next node.
/** * Base for iterators that handle predicates. Does the basic next * node logic, so all the derived iterator has to do is get the * next node. */
public abstract class BasicTestIterator extends LocPathIterator { static final long serialVersionUID = 3505378079378096623L;
Create a LocPathIterator object.
Params:
  • nscontext – The namespace context for this iterator, should be OK if null.
/** * Create a LocPathIterator object. * * @param nscontext The namespace context for this iterator, * should be OK if null. */
protected BasicTestIterator() { }
Create a LocPathIterator object.
Params:
  • nscontext – The namespace context for this iterator, should be OK if null.
/** * Create a LocPathIterator object. * * @param nscontext The namespace context for this iterator, * should be OK if null. */
protected BasicTestIterator(PrefixResolver nscontext) { super(nscontext); }
Create a LocPathIterator object, including creation of step walkers from the opcode list, and call back into the Compiler to create predicate expressions.
Params:
  • compiler – The Compiler which is creating this expression.
  • opPos – The position of this iterator in the opcode list from the compiler.
Throws:
/** * Create a LocPathIterator object, including creation * of step walkers from the opcode list, and call back * into the Compiler to create predicate expressions. * * @param compiler The Compiler which is creating * this expression. * @param opPos The position of this iterator in the * opcode list from the compiler. * * @throws javax.xml.transform.TransformerException */
protected BasicTestIterator(Compiler compiler, int opPos, int analysis) throws javax.xml.transform.TransformerException { super(compiler, opPos, analysis, false); int firstStepPos = OpMap.getFirstChildPos(opPos); int whatToShow = compiler.getWhatToShow(firstStepPos); if ((0 == (whatToShow & (DTMFilter.SHOW_ATTRIBUTE | DTMFilter.SHOW_NAMESPACE | DTMFilter.SHOW_ELEMENT | DTMFilter.SHOW_PROCESSING_INSTRUCTION))) || (whatToShow == DTMFilter.SHOW_ALL)) initNodeTest(whatToShow); else { initNodeTest(whatToShow, compiler.getStepNS(firstStepPos), compiler.getStepLocalName(firstStepPos)); } initPredicateInfo(compiler, firstStepPos); }
Create a LocPathIterator object, including creation of step walkers from the opcode list, and call back into the Compiler to create predicate expressions.
Params:
  • compiler – The Compiler which is creating this expression.
  • opPos – The position of this iterator in the opcode list from the compiler.
  • shouldLoadWalkers – True if walkers should be loaded, or false if this is a derived iterator and it doesn't wish to load child walkers.
Throws:
/** * Create a LocPathIterator object, including creation * of step walkers from the opcode list, and call back * into the Compiler to create predicate expressions. * * @param compiler The Compiler which is creating * this expression. * @param opPos The position of this iterator in the * opcode list from the compiler. * @param shouldLoadWalkers True if walkers should be * loaded, or false if this is a derived iterator and * it doesn't wish to load child walkers. * * @throws javax.xml.transform.TransformerException */
protected BasicTestIterator( Compiler compiler, int opPos, int analysis, boolean shouldLoadWalkers) throws javax.xml.transform.TransformerException { super(compiler, opPos, analysis, shouldLoadWalkers); }
Get the next node via getNextXXX. Bottlenecked for derived class override.
Returns:The next node on the axis, or DTM.NULL.
/** * Get the next node via getNextXXX. Bottlenecked for derived class override. * @return The next node on the axis, or DTM.NULL. */
protected abstract int getNextNode();
Returns the next node in the set and advances the position of the iterator in the set. After a NodeIterator is created, the first call to nextNode() returns the first node in the set.
Returns: The next Node in the set being iterated over, or null if there are no more members in that set.
/** * Returns the next node in the set and advances the position of the * iterator in the set. After a NodeIterator is created, the first call * to nextNode() returns the first node in the set. * * @return The next <code>Node</code> in the set being iterated over, or * <code>null</code> if there are no more members in that set. */
public int nextNode() { if(m_foundLast) { m_lastFetched = DTM.NULL; return DTM.NULL; } if(DTM.NULL == m_lastFetched) { resetProximityPositions(); } int next; com.sun.org.apache.xpath.internal.VariableStack vars; int savedStart; if (-1 != m_stackFrame) { vars = m_execContext.getVarStack(); // These three statements need to be combined into one operation. savedStart = vars.getStackFrame(); vars.setStackFrame(m_stackFrame); } else { // Yuck. Just to shut up the compiler! vars = null; savedStart = 0; } try { do { next = getNextNode(); if (DTM.NULL != next) { if(DTMIterator.FILTER_ACCEPT == acceptNode(next)) break; else continue; } else break; } while (next != DTM.NULL); if (DTM.NULL != next) { m_pos++; return next; } else { m_foundLast = true; return DTM.NULL; } } finally { if (-1 != m_stackFrame) { // These two statements need to be combined into one operation. vars.setStackFrame(savedStart); } } }
Get a cloned Iterator that is reset to the beginning of the query. @return A cloned NodeIterator set of the start of the query. @throws CloneNotSupportedException
/** * Get a cloned Iterator that is reset to the beginning * of the query. * * @return A cloned NodeIterator set of the start of the query. * * @throws CloneNotSupportedException */
public DTMIterator cloneWithReset() throws CloneNotSupportedException { ChildTestIterator clone = (ChildTestIterator) super.cloneWithReset(); clone.resetProximityPositions(); return clone; } }