/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.uima.fsvars.impl;
import java.util.ArrayList;
import java.util.List;
import org.apache.uima.cas.CAS;
import org.apache.uima.cas.FSIndex;
import org.apache.uima.cas.FSIterator;
import org.apache.uima.cas.Feature;
import org.apache.uima.cas.FeatureStructure;
import org.apache.uima.cas.Type;
import org.apache.uima.cas.TypeSystem;
import org.apache.uima.fsvars.FsVariables;
import org.apache.uima.fsvars.FsVariablesException;
/**
* TODO: Create type commment.
*/
public class FsVariablesImpl implements FsVariables {
private static final String messageCatalog = "org.apache.uima.fsvars.messages";
private CAS cas;
private FSIndex index;
private Type fsVariableType;
private Feature nameFeature;
private Feature typeFeature;
private Feature valueFeature;
public FsVariablesImpl() {
super();
}
public void declareFsVariable(String name, Type type) {
// If a fsvar of that name already exists, throw an exception.
if (isFsVariable(name)) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_variable_already_defined, new Object[] { name });
}
// Create the FS.
FeatureStructure fs = this.cas.createFS(this.fsVariableType);
// Set name and type features.
fs.setStringValue(this.nameFeature, name);
fs.setStringValue(this.typeFeature, type.getName());
// Add to the index.
this.cas.addFsToIndexes(fs);
}
public Type getFsVariableType(String name) {
// Try to retrieve the fsvar of "name". Will throw exception if fsvar doesn't exist.
FeatureStructure fs = getFsVarForName(name);
// Get the type name, and corresponding type.
String typeName = fs.getStringValue(this.typeFeature);
Type type = this.cas.getTypeSystem().getType(typeName);
// Check that the type name is valid.
if (type == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.bad_typename_in_fsvar, new Object[] { typeName, name });
}
return type;
}
public FeatureStructure getVariableValue(String name) {
// Try to retrieve the fsvar of "name".
FeatureStructure fsvar = getFsVarForName(name);
return fsvar.getFeatureValue(this.valueFeature);
}
public boolean isFsVariable(String name) {
// Get candidate FS.
FeatureStructure fs = getFsVarNoExc(name);
// Check that candidate is valid.
return ((fs != null) && fs.getStringValue(this.nameFeature).equals(name));
}
public List listFsVariables() {
List list = new ArrayList();
// Iterate over fsvars and add names to list.
for (FSIterator it = this.index.iterator(); it.isValid(); it.moveToNext()) {
list.add(it.get().getStringValue(this.nameFeature));
}
return list;
}
public List listFsVariables(Type type) {
List list = new ArrayList();
TypeSystem ts = this.cas.getTypeSystem();
// Iterate over fsvars and add names to list.
for (FSIterator it = this.index.iterator(); it.isValid(); it.moveToNext()) {
String typeName = it.get().getStringValue(this.typeFeature);
if (ts.subsumes(type, ts.getType(typeName))) {
list.add(it.get().getStringValue(this.nameFeature));
}
}
return list;
}
public void setVariable(String name, FeatureStructure fs) {
// Get fsvar (must exist).
FeatureStructure fsvar = getFsVarForName(name);
// Get type of fsvar.
Type type = this.cas.getTypeSystem().getType(fsvar.getStringValue(this.typeFeature));
if (type == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.bad_typename_in_fsvar, new Object[] {
fsvar.getStringValue(this.nameFeature), name });
}
if (this.cas.getTypeSystem().subsumes(type, fs.getType())) {
// Set variable value if type of var subsumes type of FS.
fsvar.setFeatureValue(this.valueFeature, fs);
} else {
// If var type does not subsume value type, throw an exception.
throw new FsVariablesException(messageCatalog,
FsVariablesException.illegal_fsvar_value, new Object[] { fs.getType().getName(), name,
type.getName() });
}
}
public void init(CAS cas) {
// Need to keep the CAS around.
this.cas = cas;
if (this.cas == null) {
throw new NullPointerException("CAS");
}
// Get the fsvars index.
this.index = this.cas.getIndexRepository().getIndex(FsVariables.INDEX_NAME);
if (this.index == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_index_doesnt_exist, new Object[] { FsVariables.INDEX_NAME });
}
// Get the fsvars type.
this.fsVariableType = this.cas.getTypeSystem().getType(FsVariables.TYPE_NAME);
if (this.fsVariableType == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_type_doesnt_exist, new Object[] { FsVariables.TYPE_NAME });
}
// Get the name, type, and value features.
this.nameFeature = this.fsVariableType.getFeatureByBaseName(FsVariables.NAME_FEATURE_NAME);
if (this.nameFeature == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_feature_doesnt_exist,
new Object[] { FsVariables.NAME_FEATURE_NAME });
}
this.typeFeature = this.fsVariableType.getFeatureByBaseName(FsVariables.TYPE_FEATURE_NAME);
if (this.typeFeature == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_feature_doesnt_exist,
new Object[] { FsVariables.TYPE_FEATURE_NAME });
}
this.valueFeature = this.fsVariableType.getFeatureByBaseName(FsVariables.VALUE_FEATURE_NAME);
if (this.valueFeature == null) {
throw new FsVariablesException(messageCatalog,
FsVariablesException.fsvars_feature_doesnt_exist,
new Object[] { FsVariables.VALUE_FEATURE_NAME });
}
}
public boolean checkCas(CAS cas) {
FSIndex variableIndex = cas.getIndexRepository().getIndex(FsVariables.INDEX_NAME);
if (variableIndex == null) {
return false;
}
TypeSystem ts = cas.getTypeSystem();
Type type = ts.getType(FsVariables.TYPE_NAME);
if (type == null) {
return false;
}
if (type.getFeatureByBaseName(FsVariables.NAME_FEATURE_NAME) == null) {
return false;
}
if (type.getFeatureByBaseName(FsVariables.VALUE_FEATURE_NAME) == null) {
return false;
}
return true;
}
private final FeatureStructure getFsVarForName(String name) {
// Get candidate FS.
FeatureStructure fs = getFsVarNoExc(name);
// Check that the fsvar FS is valid (not null and correct name)
if ((fs != null) && fs.getStringValue(this.nameFeature).equals(name)) {
return fs;
}
// If fsvar with "name" exists, throw an exception.
throw new FsVariablesException(messageCatalog,
FsVariablesException.no_such_fsvar, new Object[] { name });
}
private final FeatureStructure getFsVarNoExc(String name) {
// Get an iterator over the fsvar index.
FSIterator it = this.index.iterator();
// Create a temp FS with which to search for the variable. We do this every time we retrieve
// a variable, so this is sort of a CAS memory leak as the storage is not reclaimed. The
// assumption is that annotators won't do this a lot.
FeatureStructure fs = this.cas.createFS(this.fsVariableType);
// Set the name of the temp var to the name we're looking for.
fs.setStringValue(this.nameFeature, name);
// Move the iterator, hopefully to the already existing var of that name.
it.moveTo(fs);
// Get the fsvar.
if (it.isValid()) {
return it.get();
}
return null;
}
}