/*
* Copyright 2013 JBoss, by Red Hat, Inc
*
* 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.jboss.errai.databinding.rebind;
import java.io.IOException;
import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.net.URL;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.PropertyResourceBundle;
import java.util.ResourceBundle;
import java.util.Set;
import org.jboss.errai.codegen.Statement;
import org.jboss.errai.codegen.Variable;
import org.jboss.errai.codegen.exception.GenerationException;
import org.jboss.errai.codegen.meta.MetaClass;
import org.jboss.errai.codegen.meta.MetaClassFactory;
import org.jboss.errai.codegen.meta.MetaConstructor;
import org.jboss.errai.codegen.meta.MetaField;
import org.jboss.errai.codegen.meta.MetaMethod;
import org.jboss.errai.codegen.meta.MetaParameter;
import org.jboss.errai.codegen.util.PrivateAccessType;
import org.jboss.errai.codegen.util.PrivateAccessUtil;
import org.jboss.errai.codegen.util.Stmt;
import org.jboss.errai.common.metadata.RebindUtils;
import org.jboss.errai.config.rebind.EnvUtil;
import org.jboss.errai.config.util.ClassScanner;
import org.jboss.errai.databinding.client.api.Bindable;
import org.jboss.errai.databinding.client.api.DataBinder;
import org.jboss.errai.ioc.rebind.ioc.injector.InjectUtil;
import org.jboss.errai.ioc.rebind.ioc.injector.api.InjectableInstance;
import org.jboss.errai.ui.shared.api.annotations.AutoBound;
import org.jboss.errai.ui.shared.api.annotations.Model;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.gwt.core.ext.GeneratorContext;
/**
* Utility to retrieve a data binder reference. The reference is either to an injected
* {@link AutoBound} data binder or to a generated data binder for an injected {@link Model}.
*
* @author Christian Sadilek <csadilek@redhat.com>
* @author Mike Brock
*/
public class DataBindingUtil {
private static final Logger log = LoggerFactory.getLogger(DataBindingUtil.class);
public static final String TRANSIENT_BINDER_VALUE = "DataModelBinder";
public static final String BINDER_MODEL_TYPE_VALUE = "DataBinderModelType";
public static final Annotation[] MODEL_QUALIFICATION = new Annotation[] {
new Model() {
@Override
public Class<? extends Annotation> annotationType() {
return Model.class;
}
}
};
/**
* Represents a reference to an injected or generated data binder.
*/
public static class DataBinderRef {
private final MetaClass dataModelType;
private final Statement valueAccessor;
public DataBinderRef(final MetaClass dataModelType, final Statement valueAccessor) {
this.dataModelType = dataModelType;
this.valueAccessor = valueAccessor;
}
public MetaClass getDataModelType() {
return dataModelType;
}
public Statement getValueAccessor() {
return valueAccessor;
}
}
/**
* Tries to find a data binder reference for either an injected {@link Model} or an injected
* {@link AutoBound} data binder.
*
* @param inst
* the injectable instance
*
* @return the data binder reference or null if not found.
*/
public static DataBinderRef lookupDataBinderRef(final InjectableInstance<?> inst) {
DataBinderRef ref = lookupBinderForModel(inst);
if (ref == null) {
ref = lookupAutoBoundBinder(inst);
}
return ref;
}
/**
* Tries to find a data binder reference for an injected {@link Model}.
*
* @param inst
* the injectable instance
*
* @return the data binder reference or null if not found.
*/
private static DataBinderRef lookupBinderForModel(final InjectableInstance<?> inst) {
Statement dataBinderRef;
MetaClass dataModelType;
InjectUtil.BeanMetric beanMetric =
InjectUtil.getFilteredBeanMetric(inst.getInjectionContext(),
inst.getInjector().getInjectedType(), Model.class);
if (!beanMetric.getAllInjectors().isEmpty()) {
final Collection<Object> allInjectors = beanMetric.getAllInjectors();
if (allInjectors.size() > 1) {
throw new GenerationException("Multiple @Models injected in " + inst.getEnclosingType());
}
else if (allInjectors.size() == 1) {
final Object injectorElement = allInjectors.iterator().next();
if (injectorElement instanceof MetaConstructor || injectorElement instanceof MetaMethod) {
final MetaParameter mp = beanMetric.getConsolidatedMetaParameters().iterator().next();
dataModelType = mp.getType();
assertTypeIsBindable(dataModelType);
dataBinderRef = inst.getTransientValue(TRANSIENT_BINDER_VALUE, DataBinder.class);
inst.ensureMemberExposed();
}
else {
final MetaField field = (MetaField) allInjectors.iterator().next();
dataModelType = field.getType();
assertTypeIsBindable(dataModelType);
dataBinderRef = inst.getTransientValue(TRANSIENT_BINDER_VALUE, DataBinder.class);
inst.getInjectionContext().addExposedField(field, PrivateAccessType.Both);
}
return new DataBinderRef(dataModelType, dataBinderRef);
}
}
else {
List<MetaField> modelFields = inst.getInjector().getInjectedType().getFieldsAnnotatedWith(Model.class);
if (!modelFields.isEmpty()) {
throw new GenerationException("Found one or more fields annotated with @Model but missing @Inject "
+ modelFields.toString());
}
List<MetaParameter> modelParameters =
inst.getInjector().getInjectedType().getParametersAnnotatedWith(Model.class);
if (!modelParameters.isEmpty()) {
throw new GenerationException(
"Found one or more constructor or method parameters annotated with @Model but missing @Inject "
+ modelParameters.toString());
}
}
return null;
}
/**
* Tries to find a reference for an injected {@link AutoBound} data binder.
*
* @return the data binder reference or null if not found.
*/
private static DataBinderRef lookupAutoBoundBinder(final InjectableInstance<?> inst) {
Statement dataBinderRef = null;
MetaClass dataModelType = null;
InjectUtil.BeanMetric beanMetric = InjectUtil.getFilteredBeanMetric(inst.getInjectionContext(),
inst.getInjector().getInjectedType(), AutoBound.class);
final Collection<Object> allInjectors = beanMetric.getAllInjectors();
if (allInjectors.size() > 1) {
throw new GenerationException("Multiple @AutoBound data binders injected in " + inst.getEnclosingType());
}
else if (allInjectors.size() == 1) {
final Object injectorElement = allInjectors.iterator().next();
if (injectorElement instanceof MetaConstructor || injectorElement instanceof MetaMethod) {
final MetaParameter mp = beanMetric.getConsolidatedMetaParameters().iterator().next();
assertTypeIsDataBinder(mp.getType());
dataModelType = (MetaClass) mp.getType().getParameterizedType().getTypeParameters()[0];
dataBinderRef = inst.getInjectionContext().getInlineBeanReference(mp);
inst.ensureMemberExposed();
}
else {
final MetaField field = (MetaField) allInjectors.iterator().next();
assertTypeIsDataBinder(field.getType());
dataModelType = (MetaClass) field.getType().getParameterizedType().getTypeParameters()[0];
dataBinderRef = Stmt.invokeStatic(inst.getInjectionContext().getProcessingContext().getBootstrapClass(),
PrivateAccessUtil.getPrivateFieldInjectorName(field),
Variable.get(inst.getInjector().getInstanceVarName()));
inst.getInjectionContext().addExposedField(field, PrivateAccessType.Both);
}
}
else {
final MetaClass declaringClass = inst.getInjector().getInjectedType();
for (final MetaField field : declaringClass.getFields()) {
if (field.isAnnotationPresent(AutoBound.class)) {
assertTypeIsDataBinder(field.getType());
dataModelType = (MetaClass) field.getType().getParameterizedType().getTypeParameters()[0];
dataBinderRef = Stmt.invokeStatic(inst.getInjectionContext().getProcessingContext().getBootstrapClass(),
PrivateAccessUtil.getPrivateFieldInjectorName(field),
Variable.get(inst.getInjector().getInstanceVarName()));
inst.getInjectionContext().addExposedField(field, PrivateAccessType.Both);
break;
}
}
}
return (dataBinderRef != null) ? new DataBinderRef(dataModelType, dataBinderRef) : null;
}
/**
* Ensures the provided type is a {@link DataBinder} and throws a {@link GenerationException} in
* case it's not.
*
* @param type
* the type to check
*/
private static void assertTypeIsDataBinder(MetaClass type) {
final MetaClass databinderMetaClass = MetaClassFactory.get(DataBinder.class);
if (!databinderMetaClass.isAssignableFrom(type)) {
throw new GenerationException("Type of @AutoBound element must be " + DataBinder.class.getName() +
" but is: " + type.getFullyQualifiedName());
}
}
/**
* Ensured the provided type is bindable and throws a {@link GenerationException} in case it's
* not.
*
* @param type
* the type to check
*/
private static void assertTypeIsBindable(MetaClass type) {
if (!type.isAnnotationPresent(Bindable.class) && !getConfiguredBindableTypes().contains(type)) {
throw new GenerationException(type.getName() + " must be a @Bindable type when used as @Model");
}
}
/**
* Returns all bindable types on the classpath.
*
* @param context
* the current generator context
*
* @return a set of meta classes representing the all bindable types (both annotated and
* configured in ErraiApp.properties).
*/
public static Set<MetaClass> getAllBindableTypes(final GeneratorContext context) {
Collection<MetaClass> annotatedBindableTypes =
ClassScanner.getTypesAnnotatedWith(Bindable.class, RebindUtils.findTranslatablePackages(context));
Set<MetaClass> bindableTypes = new HashSet<MetaClass>(annotatedBindableTypes);
bindableTypes.addAll(DataBindingUtil.getConfiguredBindableTypes());
return bindableTypes;
}
/**
* Reads bindable types from all ErraiApp.properties files on the classpath.
*
* @return a set of meta classes representing the configured bindable types.
*/
public static Set<MetaClass> getConfiguredBindableTypes() {
final Set<MetaClass> bindableTypes = new HashSet<MetaClass>();
final Collection<URL> erraiAppProperties = EnvUtil.getErraiAppProperties();
for (URL url : erraiAppProperties) {
InputStream inputStream = null;
try {
log.debug("Checking " + url.getFile() + " for bindable types...");
inputStream = url.openStream();
final ResourceBundle props = new PropertyResourceBundle(inputStream);
for (final String key : props.keySet()) {
if (key.equals("errai.ui.bindableTypes")) {
for (final String s : props.getString(key).split(" ")) {
try {
bindableTypes.add(MetaClassFactory.get(s.trim()));
}
catch (Exception e) {
throw new RuntimeException("Could not find class defined in ErraiApp.properties as bindable type: " + s);
}
}
break;
}
}
}
catch (IOException e) {
throw new RuntimeException("Error reading ErraiApp.properties", e);
}
finally {
if (inputStream != null) {
try {
inputStream.close();
}
catch (IOException e) {
log.warn("Failed to close input stream", e);
}
}
}
}
return bindableTypes;
}
}