| /* |
| * 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.openjpa.jdbc.kernel.exps; |
| |
| import java.util.LinkedList; |
| import java.util.ListIterator; |
| |
| import org.apache.openjpa.jdbc.sql.SQLBuffer; |
| import org.apache.openjpa.jdbc.sql.Select; |
| import org.apache.openjpa.kernel.Broker; |
| import org.apache.openjpa.kernel.Filters; |
| import org.apache.openjpa.kernel.OpenJPAStateManager; |
| import org.apache.openjpa.kernel.exps.Context; |
| import org.apache.openjpa.kernel.exps.ExpressionVisitor; |
| import org.apache.openjpa.meta.ClassMetaData; |
| import org.apache.openjpa.meta.FieldMetaData; |
| import org.apache.openjpa.meta.XMLMetaData; |
| import org.apache.openjpa.util.ImplHelper; |
| import org.apache.openjpa.util.InternalException; |
| |
| /** |
| * A field traversal starting with a constant filter parameter. |
| * |
| * @author Abe White |
| */ |
| class ConstPath |
| extends Const |
| implements JDBCPath { |
| |
| |
| private static final long serialVersionUID = 1L; |
| private final Const _constant; |
| private final LinkedList _actions = new LinkedList(); |
| |
| /** |
| * Constructor. Supply constant to traverse. |
| */ |
| public ConstPath(Const constant) { |
| _constant = constant; |
| } |
| |
| @Override |
| public Class getType() { |
| if (_actions.isEmpty()) { |
| ClassMetaData meta = getMetaData(); |
| if (meta == null) |
| return Object.class; |
| return meta.getDescribedType(); |
| } |
| |
| Object last = _actions.getLast(); |
| if (last instanceof Class) |
| return (Class) last; |
| FieldMetaData fmd = (FieldMetaData) last; |
| return fmd.getDeclaredType(); |
| } |
| |
| @Override |
| public void setImplicitType(Class type) { |
| _actions.add(type); |
| } |
| |
| @Override |
| public void get(FieldMetaData field, boolean nullTraversal) { |
| _actions.add(field); |
| } |
| |
| @Override |
| public void getKey() { |
| } |
| |
| @Override |
| public FieldMetaData last() { |
| ListIterator itr = _actions.listIterator(_actions.size()); |
| Object prev; |
| while (itr.hasPrevious()) { |
| prev = itr.previous(); |
| if (prev instanceof FieldMetaData) |
| return (FieldMetaData) prev; |
| } |
| return null; |
| } |
| |
| @Override |
| public Object getValue(Object[] params) { |
| throw new InternalException(); |
| } |
| |
| @Override |
| public Object getValue(ExpContext ctx, ExpState state) { |
| return ((ConstPathExpState) state).value; |
| } |
| |
| @Override |
| public Object getSQLValue(Select sel, ExpContext ctx, ExpState state) { |
| return ((ConstPathExpState) state).sqlValue; |
| } |
| |
| @Override |
| public ExpState initialize(Select sel, ExpContext ctx, int flags) { |
| return new ConstPathExpState(_constant.initialize(sel, ctx, 0)); |
| } |
| |
| @Override |
| public void calculateValue(Select sel, ExpContext ctx, ExpState state, |
| Val other, ExpState otherState) { |
| super.calculateValue(sel, ctx, state, other, otherState); |
| ConstPathExpState cstate = (ConstPathExpState) state; |
| _constant.calculateValue(sel, ctx, cstate.constantState, null, null); |
| cstate.value = _constant.getValue(ctx, cstate.constantState); |
| boolean failed = false; |
| |
| // copied from org.apache.openjpa.query.InMemoryPath |
| Object action; |
| OpenJPAStateManager sm; |
| Broker tmpBroker = null; |
| for (Object o : _actions) { |
| // fail on null value |
| if (cstate.value == null) { |
| failed = true; |
| break; |
| } |
| |
| action = o; |
| if (action instanceof Class) { |
| try { |
| cstate.value = Filters.convert(cstate.value, |
| (Class) action); |
| continue; |
| } |
| catch (ClassCastException cce) { |
| failed = true; |
| break; |
| } |
| } |
| |
| // make sure we can access the instance; even non-pc vals might |
| // be proxyable |
| sm = null; |
| tmpBroker = null; |
| if (ImplHelper.isManageable(cstate.value)) |
| sm = (OpenJPAStateManager) (ImplHelper.toPersistenceCapable( |
| cstate.value, |
| this.getMetaData().getRepository().getConfiguration())). |
| pcGetStateManager(); |
| if (sm == null) { |
| tmpBroker = ctx.store.getContext().getBroker(); |
| tmpBroker.transactional(cstate.value, false, null); |
| sm = tmpBroker.getStateManager(cstate.value); |
| } |
| |
| try { |
| // get the specified field value and switch candidate |
| cstate.value = sm.fetchField(((FieldMetaData) action). |
| getIndex(), true); |
| } |
| finally { |
| // setTransactional does not clear the state, which is |
| // important since tmpVal might be also managed by |
| // another broker if it's a proxied non-pc instance |
| if (tmpBroker != null) |
| tmpBroker.nontransactional(sm.getManagedInstance(), null); |
| } |
| } |
| |
| if (failed) |
| cstate.value = null; |
| |
| if (other != null) { |
| cstate.sqlValue = other.toDataStoreValue(sel, ctx, otherState, |
| cstate.value); |
| cstate.otherLength = other.length(sel, ctx, otherState); |
| } else |
| cstate.sqlValue = cstate.value; |
| } |
| |
| @Override |
| public void appendTo(Select sel, ExpContext ctx, ExpState state, |
| SQLBuffer sql, int index) { |
| ConstPathExpState cstate = (ConstPathExpState) state; |
| if (cstate.otherLength > 1) |
| sql.appendValue(((Object[]) cstate.sqlValue)[index], |
| cstate.getColumn(index)); |
| else |
| sql.appendValue(cstate.sqlValue, cstate.getColumn(index)); |
| } |
| |
| @Override |
| public void acceptVisit(ExpressionVisitor visitor) { |
| visitor.enter(this); |
| _constant.acceptVisit(visitor); |
| visitor.exit(this); |
| } |
| |
| /** |
| * Expression state. |
| */ |
| private static class ConstPathExpState |
| extends ConstExpState { |
| |
| public final ExpState constantState; |
| public Object value = null; |
| public Object sqlValue = null; |
| public int otherLength = 0; |
| |
| public ConstPathExpState(ExpState constantState) { |
| this.constantState = constantState; |
| } |
| } |
| |
| @Override |
| public void get(FieldMetaData fmd, XMLMetaData meta) { |
| } |
| |
| @Override |
| public void get(XMLMetaData meta, String name) { |
| } |
| |
| @Override |
| public XMLMetaData getXmlMapping() { |
| return null; |
| } |
| |
| @Override |
| public void setSchemaAlias(String schemaAlias) { |
| } |
| |
| @Override |
| public String getSchemaAlias() { |
| return null; |
| } |
| |
| @Override |
| public void setSubqueryContext(Context conext, String correlationVar) { |
| } |
| |
| @Override |
| public String getCorrelationVar() { |
| return null; |
| } |
| } |