/*
* Copyright 2013 <a href="mailto:lincolnbaxter@gmail.com">Lincoln Baxter, III</a>
*
* 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.ocpsoft.rewrite.util;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import org.ocpsoft.rewrite.bind.Binding;
import org.ocpsoft.rewrite.bind.Evaluation;
import org.ocpsoft.rewrite.config.Operation;
import org.ocpsoft.rewrite.context.EvaluationContext;
import org.ocpsoft.rewrite.event.Rewrite;
import org.ocpsoft.rewrite.exception.RewriteException;
import org.ocpsoft.rewrite.param.DefaultParameter;
import org.ocpsoft.rewrite.param.DefaultParameterStore;
import org.ocpsoft.rewrite.param.Parameter;
import org.ocpsoft.rewrite.param.ParameterStore;
import org.ocpsoft.rewrite.param.Parameterized;
/**
* Utility methods for interactive with {@link ParameterStore} instances.
*
* @author <a href="mailto:lincolnbaxter@gmail.com">Lincoln Baxter, III</a>
*/
public class ParameterUtils
{
/**
* Initialize the {@link Parameterized} instance with the {@link ParameterStore} from the given
* {@link EvaluationContext}, also record required parameter names in the {@link ParameterStore} and initialize with
* a new {@link Parameter} instance.
*/
public static void initialize(EvaluationContext context, Object parameterized)
{
initialize(DefaultParameterStore.getInstance(context), parameterized);
}
/**
* Initialize the {@link Parameterized} instance with the given {@link ParameterStore}, also record required
* parameter names in the {@link ParameterStore} and initialize with a new {@link Parameter} instance.
*/
public static void initialize(ParameterStore store, Object parameterized)
{
if (parameterized instanceof Parameterized)
{
Set<String> names = ((Parameterized) parameterized).getRequiredParameterNames();
for (String name : names) {
store.get(name, new DefaultParameter(name));
}
((Parameterized) parameterized).setParameterStore(store);
}
}
/**
* Submit the given value to all registered {@link Binding} instances of the given {@link Parameter}. Perform this by
* adding individual {@link BindingOperation} instances via {@link EvaluationContext#addPreOperation(Operation)}
*/
public static boolean enqueueSubmission(final Rewrite event, final EvaluationContext context,
final Parameter<?> parameter, final Object value)
{
if (value == null)
return true;
List<Operation> operations = new ArrayList<Operation>();
List<Binding> bindings = parameter.getBindings();
for (Binding binding : bindings) {
try {
if (binding instanceof Evaluation)
{
/*
* Binding to the EvaluationContext is available immediately.
*/
Object convertedValue = ValueHolderUtil.convert(event, context, parameter.getConverter(), value);
if (ValueHolderUtil.validates(event, context, parameter.getValidator(), convertedValue))
{
Evaluation evaluation = (Evaluation) binding;
evaluation.submit(event, context, value);
evaluation.submitConverted(event, context, convertedValue);
}
else
return false;
}
else
{
Object convertedValue = ValueHolderUtil.convert(event, context, parameter.getConverter(), value);
if (ValueHolderUtil.validates(event, context, parameter.getValidator(), convertedValue))
{
operations.add(new BindingOperation(binding, convertedValue));
}
else
return false;
}
}
catch (Exception e) {
throw new RewriteException("Failed to bind value [" + value + "] to binding [" + binding + "]", e);
}
}
for (Operation operation : operations) {
context.addPreOperation(operation);
}
return true;
}
/**
* Extract bound values from configured {@link Parameter} instances. Return a {@link List} of the extracted values.
*/
public static Object performRetrieval(final Rewrite event, final EvaluationContext context,
final Parameter<?> parameter)
{
Object result = null;
List<Binding> bindings = new ArrayList<Binding>(parameter.getBindings());
Collections.reverse(bindings);
// FIXME Should not have to worry about order here.
for (Binding binding : bindings)
{
if (result == null && !(binding instanceof Evaluation) && binding.supportsRetrieval())
{
result = binding.retrieve(event, context);
}
}
for (Binding binding : bindings)
{
if (binding instanceof Evaluation)
{
if (((Evaluation) binding).hasValue(event, context))
{
result = binding.retrieve(event, context);
}
}
}
return result;
}
/**
* Used to store bindings until all conditions have been met.
*
* @author <a href="mailto:lincolnbaxter@gmail.com">Lincoln Baxter, III</a>
*/
private static class BindingOperation implements Operation
{
private final Binding binding;
private final Object value;
public BindingOperation(final Binding binding, final Object value)
{
this.binding = binding;
this.value = value;
}
@Override
public void perform(final Rewrite event, final EvaluationContext context)
{
binding.submit(event, context, value);
}
@Override
public String toString()
{
return "BindingOperation [binding=" + binding + ", value=" + value + "]";
}
}
}