org.modeshape.jcr.query.RowExtractors Maven / Gradle / Ivy
/*
* ModeShape (http://www.modeshape.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.modeshape.jcr.query;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import org.modeshape.common.util.CheckArg;
import org.modeshape.jcr.api.Binary;
import org.modeshape.jcr.cache.CachedNode;
import org.modeshape.jcr.cache.NodeCache;
import org.modeshape.jcr.cache.NodeKey;
import org.modeshape.jcr.query.NodeSequence.Batch;
import org.modeshape.jcr.query.NodeSequence.RowAccessor;
import org.modeshape.jcr.query.model.DynamicOperand;
import org.modeshape.jcr.query.model.NullOrder;
import org.modeshape.jcr.query.model.Order;
import org.modeshape.jcr.query.model.TypeSystem;
import org.modeshape.jcr.query.model.TypeSystem.TypeFactory;
import org.modeshape.jcr.value.BinaryValue;
import org.modeshape.jcr.value.InvalidPathException;
import org.modeshape.jcr.value.Name;
import org.modeshape.jcr.value.Path;
import org.modeshape.jcr.value.Property;
import org.modeshape.jcr.value.binary.BinaryStore;
import org.modeshape.jcr.value.binary.BinaryStoreException;
/**
* Standard {@link ExtractFromRow} implementations.
*
* @author Randall Hauch ([email protected])
*/
public class RowExtractors {
/**
* Obtain a new {@link ExtractFromRow} instance that uses the supplied row extractor but converts the value to the supplied
* type.
*
* @param extractor the extractor that obtains a value from the row; may not be null
* @param newType the factory for the desired type; may not be null
* @return the converting row extractor instance; never null
*/
public static ExtractFromRow convert( final ExtractFromRow extractor,
final TypeFactory newType ) {
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return newType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
Object value = extractor.getValueInRow(row);
if (value == null) return value;
if (value instanceof Object[]) {
Object[] values = (Object[])value;
for (int i = 0; i != values.length; ++i) {
values[i] = newType.create(values[i]);
}
return values;
}
return newType.create(extractor.getValueInRow(row));
}
@Override
public String toString() {
return "(as-string " + extractor.toString() + " )";
}
};
}
/**
* Obtain a new {@link ExtractFromRow} instance that will extract the full text for a node.
*
* Note that if the node is null at the specified index in the row, the extractor's
* {@link ExtractFromRow#getValueInRow(RowAccessor)} will return null.
*
*
* @param indexInRow the index of the selector in the row; presumed to be valid
* @param cache the node cache; may not be null
* @param types the system of types; may not be null
* @param binaries the binary store; may not be null
* @return the object that extracts a value from the row; never null
*/
public static ExtractFromRow extractFullText( final int indexInRow,
final NodeCache cache,
TypeSystem types,
final BinaryStore binaries ) {
final TypeFactory type = types.getStringFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
StringBuilder fullTextString = new StringBuilder();
Name name = node.getName(cache);
fullTextString.append(name.getLocalName());
Iterator iter = node.getProperties(cache);
while (iter.hasNext()) {
extractFullTextFrom(iter.next(), type, fullTextString, binaries, node, cache);
}
if (trace) NodeSequence.LOGGER.trace("Extracting full-text from {0}: {1}", node.getPath(cache), fullTextString);
// There should always be some content, since every node except the root has a name and even the
// root node has some properties that will be converted to full-text ...
return fullTextString.toString();
}
@Override
public String toString() {
return "(extract-full-text)";
}
};
}
/**
* Obtain a new {@link ExtractFromRow} instance that will extract the full text for a single property of a node.
*
* Note that if the named property does not exist on a node or the node is null at the specified index in the row, the
* extractor's {@link ExtractFromRow#getValueInRow(RowAccessor)} will return null.
*
*
* @param indexInRow the index of the selector in the row; presumed to be valid
* @param cache the node cache; may not be null
* @param propertyName the name of the property from which the full text is to be extracted; may not be null
* @param types the system of types; may not be null
* @param binaries the binary store; may not be null
* @return the object that extracts a value from the row; never null
*/
public static ExtractFromRow extractFullText( final int indexInRow,
final NodeCache cache,
final Name propertyName,
TypeSystem types,
final BinaryStore binaries ) {
final TypeFactory type = types.getStringFactory();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
Property prop = node.getProperty(propertyName, cache);
if (prop == null || prop.isEmpty()) return null;
StringBuilder fullTextString = new StringBuilder();
extractFullTextFrom(prop, type, fullTextString, binaries, node, cache);
return fullTextString.toString();
}
@Override
public String toString() {
return "(extract-full-text property=" + type.create(propertyName) + ")";
}
};
}
protected static void extractFullTextFrom( Property property,
TypeFactory type,
StringBuilder fullTextString,
BinaryStore binaries,
CachedNode node,
NodeCache cache ) {
for (Object value : property) {
extractFullTextFrom(value, type, binaries, fullTextString);
}
}
public static void extractFullTextFrom( Object propertyValue,
TypeFactory type,
BinaryStore binaries,
StringBuilder fullTextString ) {
if (propertyValue instanceof Binary && binaries != null) {
// Try extracting the text from the binary value ...
try {
propertyValue = binaries.getText((BinaryValue)propertyValue);
} catch (BinaryStoreException e) {
NodeSequence.LOGGER.debug("Error getting full text from binary {0}", propertyValue);
}
}
if (propertyValue != null) {
// Convert all other types to a string ...
fullTextString.append(' ').append(type.create(propertyValue));
}
}
/**
* Create an extractor that extracts the {@link NodeKey} from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the node key extractor; never null
*/
public static ExtractFromRow extractNodeKey( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getStringFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
if (trace) NodeSequence.LOGGER.trace("Extracting node key from {0}: {1}", node.getPath(cache), node.getKey());
return node.getKey().toString();
}
@Override
public String toString() {
return "(extract-node-key)";
}
};
}
/**
* Create an extractor that extracts the parent's {@link NodeKey} from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the node key extractor; never null
*/
public static ExtractFromRow extractParentNodeKey( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getStringFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
NodeKey parentKey = node.getParentKey(cache);
if (trace) NodeSequence.LOGGER.trace("Extracting parent key from {0}: {1}", node.getPath(cache), parentKey);
return parentKey != null ? parentKey.toString() : null;
}
@Override
public String toString() {
return "(extract-parent-key)";
}
};
}
/**
* Create an extractor that extracts the path from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractPath( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getPathFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
Path path = node.getPath(cache);
if (trace) NodeSequence.LOGGER.trace("Extracting path from {0}", path);
return path;
}
@Override
public String toString() {
return "(extract-path)";
}
};
}
/**
* Create an extractor that extracts the parent path from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractParentPath( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getPathFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
NodeKey parentKey = node.getParentKey(cache);
if (parentKey == null) return null;
CachedNode parent = cache.getNode(parentKey);
if (parent == null) return null;
Path parentPath = parent.getPath(cache);
if (trace) NodeSequence.LOGGER.trace("Extracting parent path from {0}: {1}", node.getPath(cache), parentPath);
return parentPath;
}
@Override
public String toString() {
return "(extract-parent-path)";
}
};
}
/**
* Create an extractor that extracts the path from the node at the given position in the row and applies the relative path.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param relativePath the relative path that should be applied to the nodes' path; may not be null and must be a valid
* relative path
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractRelativePath( final int indexInRow,
final Path relativePath,
final NodeCache cache,
TypeSystem types ) {
CheckArg.isNotNull(relativePath, "relativePath");
final TypeFactory type = types.getPathFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
Path nodePath = node.getPath(cache);
try {
Path path = nodePath.resolve(relativePath);
if (trace) NodeSequence.LOGGER.trace("Extracting relative path {2} from {0}: {2}", node.getPath(cache),
relativePath, path);
return path;
} catch (InvalidPathException e) {
return null;
}
}
@Override
public String toString() {
return "(extract-relative-path)";
}
};
}
/**
* Create an extractor that extracts the name from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractName( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getNameFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
Name name = node.getName(cache);
if (trace) NodeSequence.LOGGER.trace("Extracting name from {0}: {1}", node.getPath(cache), name);
return name;
}
@Override
public String toString() {
return "(extract-name)";
}
};
}
/**
* Create an extractor that extracts the name from the node at the given position in the row.
*
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param types the type system; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractLocalName( final int indexInRow,
final NodeCache cache,
TypeSystem types ) {
final TypeFactory type = types.getStringFactory();
final boolean trace = NodeSequence.LOGGER.isTraceEnabled();
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
String name = node.getName(cache).getLocalName();
if (trace) NodeSequence.LOGGER.trace("Extracting name from {0}: {1}", node.getPath(cache), name);
return name;
}
@Override
public String toString() {
return "(extract-local-name)";
}
};
}
/**
* Create an extractor that extracts an object that uniquely identifies the row. The object will be either a {@link NodeKey}
* (if rowWidth is 1), or a {@link Tuples tuple} containing each of the {@link NodeKey}s of the nodes in the row. Note that
* any of the node keys can be null, but this extractor will never return a null object.
*
* @param rowWidth the number of nodes in each row; must be positive
* @param types the types system; may not be null
* @return the extractor; never null
*/
public static ExtractFromRow extractUniqueKey( final int rowWidth,
TypeSystem types ) {
final TypeFactory keyType = types.getNodeKeyFactory();
assert rowWidth > 0;
if (rowWidth == 1) {
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return keyType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return NodeSequence.keyFor(row.getNode());
}
@Override
public String toString() {
return "(extract-key-for-order-1-tuples)";
}
};
}
if (rowWidth == 2) {
final TypeFactory tupleType = Tuples.typeFactory(keyType, keyType);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return tupleType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(NodeSequence.keyFor(row.getNode(0)), NodeSequence.keyFor(row.getNode(1)));
}
@Override
public String toString() {
return "(extract-key-for-order-2-tuples)";
}
};
}
if (rowWidth == 3) {
final TypeFactory tupleType = Tuples.typeFactory(keyType, keyType, keyType);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return tupleType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(NodeSequence.keyFor(row.getNode(0)), NodeSequence.keyFor(row.getNode(1)),
NodeSequence.keyFor(row.getNode(2)));
}
@Override
public String toString() {
return "(extract-key-for-order-3-tuples)";
}
};
}
if (rowWidth == 4) {
final TypeFactory tupleType = Tuples.typeFactory(keyType, keyType, keyType, keyType);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return tupleType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(NodeSequence.keyFor(row.getNode(0)), NodeSequence.keyFor(row.getNode(1)),
NodeSequence.keyFor(row.getNode(2)), NodeSequence.keyFor(row.getNode(3)));
}
@Override
public String toString() {
return "(extract-key-for-order-4-tuples)";
}
};
}
final TypeFactory tupleType = Tuples.typeFactory(keyType, rowWidth);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return tupleType;
}
@Override
public Object getValueInRow( RowAccessor row ) {
Object[] keys = new Object[rowWidth];
for (int i = 0; i != rowWidth; ++i) {
keys[i] = NodeSequence.keyFor(row.getNode(i));
}
return Tuples.tuple(keys);
}
@Override
public String toString() {
return "(extract-key-for-order-N-tuples)";
}
};
}
/**
* Create an extractor that extracts the property value from the node at the given position in the row.
*
* @param propertyName the name of the property; may not be null
* @param indexInRow the index of the node in the rows; must be valid
* @param cache the cache containing the nodes; may not be null
* @param desiredType the desired type, which should be converted from the actual value; may not be null
* @return the path extractor; never null
*/
public static ExtractFromRow extractPropertyValue( final Name propertyName,
final int indexInRow,
final NodeCache cache,
final TypeFactory desiredType ) {
return new ExtractFromRow() {
@Override
public Object getValueInRow( RowAccessor row ) {
CachedNode node = row.getNode(indexInRow);
if (node == null) return null;
org.modeshape.jcr.value.Property prop = node.getProperty(propertyName, cache);
return prop == null ? null : desiredType.create(prop.getFirstValue());
}
@Override
public TypeFactory getType() {
return desiredType;
}
};
}
/**
* Obtain an extractor of a tuple containing each of the values from the supplied extractors.
*
* @param first the first extractor; may not be null
* @param second the second extractor; may not be null
* @return the tuple extractor
*/
public static ExtractFromRow extractorWith( final ExtractFromRow first,
final ExtractFromRow second ) {
final TypeFactory type = Tuples.typeFactory(first.getType(), second.getType());
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(first.getValueInRow(row), second.getValueInRow(row));
}
};
}
/**
* Obtain an extractor of a tuple containing each of the values from the supplied extractors.
*
* @param first the first extractor; may not be null
* @param second the second extractor; may not be null
* @param third the third extractor; may not be null
* @return the tuple extractor
*/
public static ExtractFromRow extractorWith( final ExtractFromRow first,
final ExtractFromRow second,
final ExtractFromRow third ) {
final TypeFactory type = Tuples.typeFactory(first.getType(), second.getType(), third.getType());
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(first.getValueInRow(row), second.getValueInRow(row), third.getValueInRow(row));
}
};
}
/**
* Obtain an extractor of a tuple containing each of the values from the supplied extractors.
*
* @param first the first extractor; may not be null
* @param second the second extractor; may not be null
* @param third the third extractor; may not be null
* @param fourth the fourth extractor; may not be null
* @return the tuple extractor
*/
public static ExtractFromRow extractorWith( final ExtractFromRow first,
final ExtractFromRow second,
final ExtractFromRow third,
final ExtractFromRow fourth ) {
final TypeFactory type = Tuples.typeFactory(first.getType(), second.getType(), third.getType(), fourth.getType());
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return Tuples.tuple(first.getValueInRow(row), second.getValueInRow(row), third.getValueInRow(row),
fourth.getValueInRow(row));
}
};
}
/**
* Obtain an extractor of a tuple containing each of the values from the supplied extractors.
*
* @param extractors the extractors; may not be null or empty
* @return the tuple extractor
*/
public static ExtractFromRow extractorWith( final Collection extractors ) {
final int len = extractors.size();
assert len > 0;
// There are a few cases where specific row extractor implementations would be better ...
if (len == 1) {
return extractors.iterator().next();
}
if (len == 2) {
Iterator iter = extractors.iterator();
ExtractFromRow first = iter.next();
ExtractFromRow second = iter.next();
return extractorWith(first, second);
}
if (len == 3) {
Iterator iter = extractors.iterator();
ExtractFromRow first = iter.next();
ExtractFromRow second = iter.next();
ExtractFromRow third = iter.next();
return extractorWith(first, second, third);
}
if (len == 4) {
Iterator iter = extractors.iterator();
ExtractFromRow first = iter.next();
ExtractFromRow second = iter.next();
ExtractFromRow third = iter.next();
ExtractFromRow fourth = iter.next();
return extractorWith(first, second, third, fourth);
}
// Okay, there are at least 4 extractors, so we need to return a general-case row extractor ...
Collection> types = new ArrayList>();
final ExtractFromRow[] extracts = new ExtractFromRow[len];
int i = 0;
for (ExtractFromRow extractor : extractors) {
extracts[i++] = extractor;
types.add(extractor.getType());
}
final TypeFactory type = Tuples.typeFactory(types);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
Object[] values = new Object[len];
for (int i = 0; i != len; ++i) {
values[i] = extracts[i].getValueInRow(row);
}
return Tuples.tuple(values);
}
};
}
/**
* Create an extractor that has a {@link ExtractFromRow#getType() type factory} with a {@link TypeFactory#getComparator()
* comparator} that sorts according to the specified order and null-order behavior.
*
* @param extractor the original extractor; may not be null
* @param order the specification of whether the comparator should order ascending or descending; may not be null
* @param nullOrder the specification of whether null values should appear first or last; may not be null
* @return the extractor that is identical except that it has an inverted comparator; never null
*/
public static ExtractFromRow extractorWith( final ExtractFromRow extractor,
final Order order,
final NullOrder nullOrder ) {
final TypeFactory type = TypeSystem.with(extractor.getType(), order, nullOrder);
return new ExtractFromRow() {
@Override
public TypeFactory getType() {
return type;
}
@Override
public Object getValueInRow( RowAccessor row ) {
return extractor.getValueInRow(row);
}
@Override
public String toString() {
return extractor.toString() + " " + order + " " + nullOrder;
}
};
}
private RowExtractors() {
}
/**
* An operation that extracts a single value from the current row in a given {@link Batch}. Note that a single instance will
* be called many times (once for each row in the batches of a {@link NodeSequence}).
*
* @author Randall Hauch ([email protected])
*/
public static interface ExtractFromRow {
/**
* Get the type of value that this extractor will return from {@link #getValueInRow}.
*
* @return the type; never null
*/
TypeFactory getType();
/**
* Evaluate the {@link DynamicOperand} against the current row in the supplied batch. Note that implementations will need
* to know whether to get the {@link Batch#getNode() only node in the row} or how to get a {@link Batch#getNode(int)} for
* a specific selector.
*
* @param row the row accessor through which the current row values can be obtained; never null
* @return the dynamic operands value for the current row; may be null
*/
Object getValueInRow( RowAccessor row );
}
}
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