/*
* Copyright 2009 Google 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 com.google.gwt.uibinder.rebind;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.typeinfo.JClassType;
import com.google.gwt.core.ext.typeinfo.JType;
import com.google.gwt.core.ext.typeinfo.TypeOracle;
import com.google.gwt.uibinder.attributeparsers.FieldReferenceConverter;
import com.google.gwt.uibinder.rebind.model.ImplicitCssResource;
import com.google.gwt.uibinder.rebind.model.OwnerClass;
import com.google.gwt.uibinder.rebind.model.OwnerField;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.Map;
import java.util.regex.Pattern;
/**
* This class handles all {@link FieldWriter} instances created for the current
* template.
*/
public class FieldManager {
static class FieldAndSource {
final FieldWriter field;
final XMLElement element;
public FieldAndSource(FieldWriter field, XMLElement element) {
this.field = field;
this.element = element;
}
}
private static final String GETTER_PREFIX = "get_";
private static final String BUILDER_PREFIX = "build_";
private static final String DUPLICATE_FIELD_ERROR = "Duplicate declaration of field %1$s.";
private static final Comparator<FieldWriter> BUILD_DEFINITION_SORT =
new Comparator<FieldWriter>() {
public int compare(FieldWriter field1, FieldWriter field2) {
// First get type precedence, if ties the field precedence is used.
int precedence = field2.getFieldType().getBuildPrecedence()
- field1.getFieldType().getBuildPrecedence();
if (precedence == 0) {
precedence = field2.getBuildPrecedence() - field1.getBuildPrecedence();
}
return precedence;
}
};
private static final Pattern JAVA_IDENTIFIER =
Pattern.compile("[\\p{L}_$][\\p{L}\\p{N}_$]*");
public static String getFieldBuilder(String fieldName) {
return String.format(BUILDER_PREFIX + "%s()", fieldName);
}
public static String getFieldGetter(String fieldName) {
return String.format(GETTER_PREFIX + "%s()", fieldName);
}
public static String stripFieldGetter(String fieldName) {
if (fieldName.startsWith(GETTER_PREFIX)) {
return fieldName.substring(GETTER_PREFIX.length());
}
return fieldName;
}
private final TypeOracle typeOracle;
private final MortalLogger logger;
/**
* Map of field name to FieldWriter. Note its a LinkedHashMap--we want to
* write these out in the order they're declared.
*/
private final LinkedHashMap<String, FieldWriter> fieldsMap =
new LinkedHashMap<String, FieldWriter>();
/**
* A stack of the fields.
*/
private final LinkedList<FieldAndSource> parsedFieldStack = new LinkedList<FieldAndSource>();
private LinkedHashMap<String, FieldReference> fieldReferences =
new LinkedHashMap<String, FieldReference>();
/**
* Counts the number of times a getter field is called, this important to
* decide which strategy to take when outputing getters and builders.
* {@see com.google.gwt.uibinder.rebind.FieldWriter#writeFieldDefinition}.
*/
private final Map<String, Integer> gettersCounter = new HashMap<String, Integer>();
/**
* Whether to use the new strategy of generating UiBinder code.
*/
private final boolean useLazyWidgetBuilders;
public FieldManager(TypeOracle typeOracle, MortalLogger logger, boolean useLazyWidgetBuilders) {
this.typeOracle = typeOracle;
this.logger = logger;
this.useLazyWidgetBuilders = useLazyWidgetBuilders;
}
/**
* Converts the given field to its getter. Example:
* <li> myWidgetX = get_myWidgetX()
* <li> f_html1 = get_f_html1()
*/
public String convertFieldToGetter(String fieldName) {
// could this conversion can be moved to FieldWriter?
if (!useLazyWidgetBuilders) {
return fieldName;
}
int count = getGetterCounter(fieldName) + 1;
gettersCounter.put(fieldName, count);
return getFieldGetter(fieldName);
}
public FieldReference findFieldReference(String expressionIn) {
String expression = expressionIn;
if (useLazyWidgetBuilders) {
expression = stripFieldGetter(expression);
}
String converted = FieldReferenceConverter.expressionToPath(expression);
return fieldReferences.get(converted);
}
/**
* Initialize with field builders the generated <b>Widgets</b> inner class.
* {@see com.google.gwt.uibinder.rebind.FieldWriter#writeFieldBuilder}.
*/
public void initializeWidgetsInnerClass(IndentedWriter w,
OwnerClass ownerClass) throws UnableToCompleteException {
FieldWriter[] fields = fieldsMap.values().toArray(
new FieldWriter[fieldsMap.size()]);
Arrays.sort(fields, BUILD_DEFINITION_SORT);
for (FieldWriter field : fields) {
int count = getGetterCounter(field.getName());
field.writeFieldBuilder(w, count, ownerClass.getUiField(field.getName()));
}
}
/**
* @param fieldName the name of the {@link FieldWriter} to find
* @return the {@link FieldWriter} instance indexed by fieldName or
* <b>null</b> in case fieldName is not found
*/
public FieldWriter lookup(String fieldName) {
return fieldsMap.get(fieldName);
}
/**
* Remove the field at the top of the {@link #parsedFieldStack}.
*/
public void pop() {
parsedFieldStack.removeFirst();
}
/**
* @param source the element this field was parsed from
* @param fieldWriter the field to push on the top of the
* {@link #parsedFieldStack}
*/
public void push(XMLElement source, FieldWriter fieldWriter) {
parsedFieldStack.addFirst(new FieldAndSource(fieldWriter, source));
}
/**
* Used to declare fields of an existing type. If your field will hold a type
* that is being generated, see {@link #registerFieldOfGeneratedType}.
* <p>
* When making a field we peek at the {@link #parsedFieldStack} to make sure
* that the field that holds the widget currently being parsed will depended
* upon the field being declared. This ensures, for example, that dom id
* fields (see {@link UiBinderWriter#declareDomIdHolder()}) used by an HTMLPanel
* will be declared before it is.
*
* @param fieldWriterType the field writer type associated
* @param fieldType the type of the new field
* @param fieldName the name of the new field
* @return a new {@link FieldWriter} instance
* @throws UnableToCompleteException on duplicate name
*/
public FieldWriter registerField(FieldWriterType fieldWriterType,
JClassType fieldType, String fieldName) throws UnableToCompleteException {
FieldWriter field = new FieldWriterOfExistingType(this,
fieldWriterType, fieldType, fieldName, logger);
return registerField(fieldName, field);
}
public FieldWriter registerField(JClassType fieldType, String fieldName)
throws UnableToCompleteException {
return registerField(FieldWriterType.DEFAULT, fieldType, fieldName);
}
public FieldWriter registerField(String type, String fieldName)
throws UnableToCompleteException {
return registerField(typeOracle.findType(type), fieldName);
}
/**
* Used to declare fields that will hold generated instances generated
* CssResource interfaces. If your field will hold a reference of an existing
* type, see {@link #registerField}. For other generated types, use
* {@link #registerFieldOfGeneratedType}
* {@link #registerFieldForGeneratedCssResource}.
* <p>
* When making a field we peek at the {@link #parsedFieldStack} to make sure
* that the field that holds the widget currently being parsed will depended
* upon the field being declared. This ensures, for example, that dom id
* fields (see {@link UiBinderWriter#declareDomIdHolder()}) used by an HTMLPanel
* will be declared before it is.
*
* @throws UnableToCompleteException on duplicate name
* @return a new {@link FieldWriter} instance
*/
public FieldWriter registerFieldForGeneratedCssResource(
ImplicitCssResource cssResource) throws UnableToCompleteException {
FieldWriter field = new FieldWriterOfGeneratedCssResource(this,
typeOracle.findType(String.class.getCanonicalName()), cssResource, logger);
return registerField(cssResource.getName(), field);
}
/**
* Register a new field for {@link com.google.gwt.uibinder.client.LazyDomElement}
* types. LazyDomElement fields can only be associated with html elements. Example:
*
* <li>LazyDomElement<DivElement> -> <div></li>
* <li>LazyDomElement<Element> -> <div></li>
* <li>LazyDomElement<SpanElement> -> <span></li>
*
* @param templateFieldType the html type to bind, eg, SpanElement, DivElement, etc
* @param ownerField the field instance
*/
public FieldWriter registerFieldForLazyDomElement(JClassType templateFieldType,
OwnerField ownerField) throws UnableToCompleteException {
if (ownerField == null) {
throw new RuntimeException("Cannot register a null owner field for LazyDomElement.");
}
FieldWriter field = new FieldWriterOfLazyDomElement(this,
templateFieldType, ownerField, logger);
return registerField(ownerField.getName(), field);
}
/**
* Used to declare fields of a type (other than CssResource) that is to be
* generated. If your field will hold a reference of an existing type, see
* {@link #registerField}. For generated CssResources, see
* {@link #registerFieldForGeneratedCssResource}.
* <p>
* When making a field we peek at the {@link #parsedFieldStack} to make sure
* that the field that holds the widget currently being parsed will depended
* upon the field being declared. This ensures, for example, that dom id
* fields (see {@link UiBinderWriter#declareDomIdHolder()}) used by an HTMLPanel
* will be declared before it is.
*
* @param assignableType class or interface extened or implemented by this
* type
* @param typeName the full qualified name for the class associated with the
* field
* @param fieldName the name of the field
* @throws UnableToCompleteException on duplicate name
* @return a new {@link FieldWriter} instance
*/
public FieldWriter registerFieldOfGeneratedType(JClassType assignableType,
String typePackage, String typeName, String fieldName)
throws UnableToCompleteException {
FieldWriter field = new FieldWriterOfGeneratedType(this, assignableType,
typePackage, typeName, fieldName, logger);
return registerField(fieldName, field);
}
/**
* Called to register a <code>{field.reference}</code> encountered during
* parsing, to be validated against the type oracle once parsing is complete.
*/
public void registerFieldReference(XMLElement source, String fieldReferenceString, JType... types) {
source = source != null ? source : parsedFieldStack.peek().element;
FieldReference fieldReference = fieldReferences.get(fieldReferenceString);
if (fieldReference == null) {
fieldReference = new FieldReference(fieldReferenceString, source, this, typeOracle);
fieldReferences.put(fieldReferenceString, fieldReference);
}
fieldReference.addLeftHandType(source, types);
}
/**
* Gets a FieldWriter given its name or throws a RuntimeException if not found.
* @param fieldName the name of the {@link FieldWriter} to find
* @return the {@link FieldWriter} instance indexed by fieldName
*/
public FieldWriter require(String fieldName) {
FieldWriter fieldWriter = lookup(fieldName);
if (fieldWriter == null) {
throw new RuntimeException("The required field %s doesn't exist.");
}
return fieldWriter;
}
/**
* To be called after parsing is complete. Surveys all
* <code>{field.reference}</code>s and checks they refer to existing types,
* and have appropriate return types.
*
* @throws UnableToCompleteException if any <code>{field.references}</code>
* can't be resolved
*/
public void validate() throws UnableToCompleteException {
boolean failed = false;
for (Map.Entry<String, FieldReference> entry : fieldReferences.entrySet()) {
FieldReference ref = entry.getValue();
MonitoredLogger monitoredLogger = new MonitoredLogger(logger);
ref.validate(monitoredLogger);
failed |= monitoredLogger.hasErrors();
}
if (failed) {
throw new UnableToCompleteException();
}
}
/**
* Outputs the getter and builder definitions for all fields.
* {@see com.google.gwt.uibinder.rebind.AbstractFieldWriter#writeFieldDefinition}.
*/
public void writeFieldDefinitions(IndentedWriter writer, TypeOracle typeOracle,
OwnerClass ownerClass, DesignTimeUtils designTime)
throws UnableToCompleteException {
Collection<FieldWriter> fields = fieldsMap.values();
for (FieldWriter field : fields) {
int counter = getGetterCounter(field.getName());
field.writeFieldDefinition(
writer,
typeOracle,
ownerClass.getUiField(field.getName()),
designTime,
counter,
useLazyWidgetBuilders);
}
}
/**
* Writes all stored gwt fields.
*
* @param writer the writer to output
*/
public void writeGwtFieldsDeclaration(IndentedWriter writer) throws UnableToCompleteException {
Collection<FieldWriter> fields = fieldsMap.values();
for (FieldWriter field : fields) {
field.write(writer);
}
}
private void ensureValidity(String fieldName) throws UnableToCompleteException {
if (!JAVA_IDENTIFIER.matcher(fieldName).matches()) {
logger.die("Illegal field name \"%s\"", fieldName);
}
}
/**
* Gets the number of times a getter for the given field is called.
*/
private int getGetterCounter(String fieldName) {
Integer count = gettersCounter.get(fieldName);
return (count == null) ? 0 : count;
}
private FieldWriter registerField(String fieldName, FieldWriter field)
throws UnableToCompleteException {
ensureValidity(fieldName);
requireUnique(fieldName);
fieldsMap.put(fieldName, field);
if (parsedFieldStack.size() > 0) {
FieldWriter parent = parsedFieldStack.peek().field;
field.setBuildPrecedence(parent.getBuildPrecedence() + 1);
parent.needs(field);
}
return field;
}
private void requireUnique(String fieldName) throws UnableToCompleteException {
if (fieldsMap.containsKey(fieldName)) {
logger.die(DUPLICATE_FIELD_ERROR, fieldName);
}
}
}