Class VirtualCopy.VirtualCopier
- java.lang.Object
-
- net.sf.saxon.tree.wrapper.VirtualCopy.VirtualCopier
-
- All Implemented Interfaces:
java.io.Closeable
,java.lang.AutoCloseable
,SequenceIterator
,AxisIterator
- Enclosing class:
- VirtualCopy
protected static class VirtualCopy.VirtualCopier extends java.lang.Object implements AxisIterator
VirtualCopier implements the XPath axes as applied to a VirtualCopy node. It works by applying the requested axis to the node of which this is a copy. There are two complications: firstly, all nodes encountered must themselves be (virtually) copied to give them a new identity. Secondly, axes that stray outside the subtree rooted at the original copied node must be truncated.
-
-
Field Summary
Fields Modifier and Type Field Description protected AxisIterator
base
protected VirtualCopy
node
protected boolean
testInclusion
-
Constructor Summary
Constructors Constructor Description VirtualCopier(VirtualCopy node, AxisIterator base, VirtualCopy parent, boolean testInclusion)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
close()
Close the iterator.void
discharge()
Calling this method instructs the iterator to release any resources it holds, while still remaining able to deliver the remaining items in the sequence.NodeInfo
next()
Get the next item in the sequence.
-
-
-
Field Detail
-
node
protected VirtualCopy node
-
base
protected AxisIterator base
-
testInclusion
protected boolean testInclusion
-
-
Constructor Detail
-
VirtualCopier
public VirtualCopier(VirtualCopy node, AxisIterator base, VirtualCopy parent, boolean testInclusion)
-
-
Method Detail
-
next
public NodeInfo next()
Get the next item in the sequence.- Specified by:
next
in interfaceAxisIterator
- Specified by:
next
in interfaceSequenceIterator
- Returns:
- the next Item. If there are no more nodes, return null.
-
close
public void close()
Description copied from interface:SequenceIterator
Close the iterator. This indicates to the supplier of the data that the client does not require any more items to be delivered by the iterator. This may enable the supplier to release resources. After calling close(), no further calls on the iterator should be made; if further calls are made, the effect of such calls is undefined.For example, the iterator returned by the unparsed-text-lines() function has a close() method that causes the underlying input stream to be closed, whether or not the file has been read to completion.
Closing an iterator is important when the data is being "pushed" in another thread. Closing the iterator terminates that thread and means that it needs to do no additional work. Indeed, failing to close the iterator may cause the push thread to hang waiting for the buffer to be emptied.
Closing an iterator is not necessary if the iterator is read to completion: if a call on
SequenceIterator.next()
returns null, the iterator will be closed automatically. An explicit call onSequenceIterator.close()
is needed only when iteration is abandoned prematurely.- Specified by:
close
in interfacejava.lang.AutoCloseable
- Specified by:
close
in interfacejava.io.Closeable
- Specified by:
close
in interfaceSequenceIterator
-
discharge
public void discharge()
Description copied from interface:SequenceIterator
Calling this method instructs the iterator to release any resources it holds, while still remaining able to deliver the remaining items in the sequence. This may require the iterator to calculate the rest of the sequence eagerly. The method is called by a client if it anticipates that it might not read the iterator to completion, but it cannot guarantee thatSequenceIterator.close()
will be called when no more items are needed.- Specified by:
discharge
in interfaceSequenceIterator
-
-