java.lang.AutoCloseable
, java.sql.ResultSet
, java.sql.Wrapper
, AwareVTI
public class XmlVTI extends StringColumnVTI
This is a VTI designed to read XML files which are structured like row sets.
XML files parsed by this VTI are always processed with external entity expansion disabled and secure parser processing enabled.
There are two invocation formats provided by this VTI.
One form of this VTI takes the following arguments. This form is useful when all of the columns in the row can be constructed from data nested INSIDE the row Element.
Here is a sample declaration of this first form of the XmlVTI:
create function findbugs( xmlResourceName varchar( 32672 ), rowTag varchar( 32672 ), childTags varchar( 32672 )... ) returns table ( className varchar( 32672 ), bugCount int ) language java parameter style derby_jdbc_result_set no sql external name 'org.apache.derby.vti.XmlVTI.xmlVTI';
...and here is a sample invocation:
create view findbugs as select * from table ( findbugs ( 'findbugs.xml', 'ClassStats', 'class', 'bugs' ) ) v; select * from findbugs where bugCount != 0;
A second form of this VTI takes the following arguments. This form is useful when some of the columns in the row are "inherited" from outer elements inside which the row element nests:
Here is a sample declaration of this second form of the XmlVTI. Using the second form involves declaring an ArrayList type and a factory method too:
create type ArrayList external name 'java.util.ArrayList' language java; create function asList( cell varchar( 32672 ) ... ) returns ArrayList language java parameter style derby no sql external name 'org.apache.derby.vti.XmlVTI.asList'; create function optTrace ( xmlResourceName varchar( 32672 ), rowTag varchar( 32672 ), parentTags ArrayList, childTags ArrayList ) returns table ( stmtID int, queryID int, complete boolean, summary varchar( 32672 ), type varchar( 50 ), estimatedCost double, estimatedRowCount int ) language java parameter style derby_jdbc_result_set no sql external name 'org.apache.derby.vti.XmlVTI.xmlVTI'; create view optTrace as select * from table ( optTrace ( '/Users/me/derby/mainline/z.xml', 'planCost', asList( 'stmtID', 'queryID', 'complete' ), asList( 'summary', 'type', 'estimatedCost', 'estimatedRowCount' ) ) ) v ; select * from optTrace where stmtID = 6 and complete order by estimatedCost;
Modifier and Type | Class | Description |
---|---|---|
private class |
XmlVTI.XMLErrorHandler |
VTITemplate.ColumnDescriptor
Modifier and Type | Field | Description |
---|---|---|
private javax.xml.parsers.DocumentBuilder |
_builder |
|
private java.lang.String[] |
_currentRow |
|
private int |
_firstChildTagIdx |
|
private org.w3c.dom.NodeList |
_rawRows |
|
private int |
_rowCount |
|
private int |
_rowIdx |
|
private java.lang.String |
_rowTag |
|
private java.io.InputStream |
_xmlResource |
Constructor | Description |
---|---|
XmlVTI(java.io.InputStream xmlResource,
java.lang.String rowTag,
int firstChildTagIdx,
java.lang.String... columnTags) |
Build an XmlVTI.
|
Modifier and Type | Method | Description |
---|---|---|
static java.util.ArrayList<java.lang.String> |
asList(java.lang.String... cells) |
Factory method to create an ArrayList
|
void |
close() |
|
private java.lang.String |
findColumnValue(org.w3c.dom.Element rawRow,
int columnNumber) |
Find the value of a column inside an element.
|
java.sql.ResultSetMetaData |
getMetaData() |
|
protected java.lang.String |
getRawColumn(int columnNumber) |
Get the string value of the column in the current row identified by the 1-based columnNumber.
|
boolean |
next() |
|
private void |
parseRow(int rowNumber) |
Parse a row into columns.
|
private void |
readRows() |
Fault in the list of rows.
|
private java.lang.String |
squeezeText(org.w3c.dom.Element node) |
Squeeze the text out of an Element.
|
private static XmlVTI |
xmlVTI(java.io.InputStream xmlResource,
java.lang.String rowTag,
java.util.ArrayList<java.lang.String> parentTags,
java.util.ArrayList<java.lang.String> childTags) |
This is the static method for creating functions from an URL and both parent and child tags
|
static XmlVTI |
xmlVTI(java.lang.String fileName,
java.lang.String rowTag,
java.lang.String... childTags) |
This is the static method for creating functions from a file name and child tags
|
static XmlVTI |
xmlVTI(java.lang.String fileName,
java.lang.String rowTag,
java.util.ArrayList<java.lang.String> parentTags,
java.util.ArrayList<java.lang.String> childTags) |
This is the static method for creating functions from a file name and both parent and child tags
|
static XmlVTI |
xmlVTIFromURL(java.lang.String urlString,
java.lang.String rowTag,
java.lang.String... childTags) |
This is the static method for creating functions from an url and child tags
|
static XmlVTI |
xmlVTIFromURL(java.lang.String urlString,
java.lang.String rowTag,
java.util.ArrayList<java.lang.String> parentTags,
java.util.ArrayList<java.lang.String> childTags) |
This is the static method for creating functions from an URL and both parent and child tags
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
updateObject, updateObject, updateObject, updateObject
findColumn, getAsciiStream, getBigDecimal, getBinaryStream, getBlob, getBoolean, getByte, getBytes, getClob, getColumnCount, getColumnName, getDate, getDouble, getFloat, getInt, getLong, getShort, getString, getTime, getTimestamp, setColumnNames, wasNull
absolute, afterLast, beforeFirst, cancelRowUpdates, clearWarnings, deleteRow, first, getArray, getArray, getAsciiStream, getBigDecimal, getBigDecimal, getBigDecimal, getBinaryStream, getBlob, getBoolean, getByte, getBytes, getCharacterStream, getCharacterStream, getClob, getConcurrency, getContext, getCursorName, getDate, getDate, getDate, getDouble, getFetchDirection, getFetchSize, getFloat, getHoldability, getInt, getLong, getNCharacterStream, getNCharacterStream, getNClob, getNClob, getNString, getNString, getObject, getObject, getObject, getObject, getObject, getObject, getRef, getRef, getReturnTableSignature, getRow, getRowId, getRowId, getShort, getSQLXML, getSQLXML, getStatement, getString, getTime, getTime, getTime, getTimestamp, getTimestamp, getTimestamp, getType, getUnicodeStream, getUnicodeStream, getURL, getURL, getWarnings, insertRow, isAfterLast, isBeforeFirst, isClosed, isFirst, isLast, isWrapperFor, last, moveToCurrentRow, moveToInsertRow, notImplemented, previous, refreshRow, relative, rowDeleted, rowInserted, rowUpdated, setContext, setFetchDirection, setFetchSize, unwrap, updateArray, updateArray, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateBigDecimal, updateBigDecimal, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBoolean, updateBoolean, updateByte, updateByte, updateBytes, updateBytes, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateClob, updateClob, updateClob, updateClob, updateClob, updateClob, updateDate, updateDate, updateDouble, updateDouble, updateFloat, updateFloat, updateInt, updateInt, updateLong, updateLong, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNString, updateNString, updateNull, updateNull, updateObject, updateObject, updateObject, updateObject, updateRef, updateRef, updateRow, updateRowId, updateRowId, updateShort, updateShort, updateSQLXML, updateSQLXML, updateString, updateString, updateTime, updateTime, updateTimestamp, updateTimestamp
private java.lang.String _rowTag
private java.io.InputStream _xmlResource
private int _rowIdx
private int _rowCount
private java.lang.String[] _currentRow
private javax.xml.parsers.DocumentBuilder _builder
private org.w3c.dom.NodeList _rawRows
private int _firstChildTagIdx
public XmlVTI(java.io.InputStream xmlResource, java.lang.String rowTag, int firstChildTagIdx, java.lang.String... columnTags)
Build an XmlVTI.
xmlResource
- The xml source as an InputStream.rowTag
- The tag of the master row Element.firstChildTagIdx
- The first (0-based) tag from columnTags which is a child tag.columnTags
- The tags which supply column data; all of the tag positions less than firstChildTagIdx come from Elements which are outer to the rowTag element; the remaining tags, starting at firstChildTagIdx, are tags of attributes or Elements inside the rowTag Element.public static XmlVTI xmlVTI(java.lang.String fileName, java.lang.String rowTag, java.lang.String... childTags) throws java.lang.Exception
java.lang.Exception
public static XmlVTI xmlVTIFromURL(java.lang.String urlString, java.lang.String rowTag, java.lang.String... childTags) throws java.lang.Exception
java.lang.Exception
public static XmlVTI xmlVTI(java.lang.String fileName, java.lang.String rowTag, java.util.ArrayList<java.lang.String> parentTags, java.util.ArrayList<java.lang.String> childTags) throws java.lang.Exception
java.lang.Exception
public static XmlVTI xmlVTIFromURL(java.lang.String urlString, java.lang.String rowTag, java.util.ArrayList<java.lang.String> parentTags, java.util.ArrayList<java.lang.String> childTags) throws java.lang.Exception
java.lang.Exception
private static XmlVTI xmlVTI(java.io.InputStream xmlResource, java.lang.String rowTag, java.util.ArrayList<java.lang.String> parentTags, java.util.ArrayList<java.lang.String> childTags) throws java.lang.Exception
java.lang.Exception
public static java.util.ArrayList<java.lang.String> asList(java.lang.String... cells)
protected java.lang.String getRawColumn(int columnNumber) throws java.sql.SQLException
Get the string value of the column in the current row identified by the 1-based columnNumber.
getRawColumn
in class StringColumnVTI
java.sql.SQLException
public void close() throws java.sql.SQLException
java.sql.SQLException
public java.sql.ResultSetMetaData getMetaData() throws java.sql.SQLException
getMetaData
in interface java.sql.ResultSet
getMetaData
in class VTITemplate
java.sql.SQLException
public boolean next() throws java.sql.SQLException
java.sql.SQLException
private void readRows() throws java.lang.Exception
Fault in the list of rows.
java.lang.Exception
private void parseRow(int rowNumber) throws java.lang.Exception
Parse a row into columns.
java.lang.Exception
private java.lang.String findColumnValue(org.w3c.dom.Element rawRow, int columnNumber) throws java.lang.Exception
Find the value of a column inside an element. The columnNumber is 0-based.
java.lang.Exception
private java.lang.String squeezeText(org.w3c.dom.Element node) throws java.lang.Exception
Squeeze the text out of an Element.
java.lang.Exception
Apache Derby V10.14 Internals - Copyright © 2004,2018 The Apache Software Foundation. All Rights Reserved.