io.protostuff.runtime.RuntimeSchema Maven / Gradle / Ivy
//========================================================================
//Copyright 2007-2009 David Yu [email protected]
//------------------------------------------------------------------------
//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 io.protostuff.runtime;
import static io.protostuff.runtime.RuntimeEnv.ID_STRATEGY;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import io.protostuff.Exclude;
import io.protostuff.Input;
import io.protostuff.Message;
import io.protostuff.Output;
import io.protostuff.Pipe;
import io.protostuff.Schema;
import io.protostuff.Tag;
import io.protostuff.runtime.RuntimeEnv.DefaultInstantiator;
import io.protostuff.runtime.RuntimeEnv.Instantiator;
/**
* A schema that can be generated and cached at runtime for objects that have no schema. This is particularly useful for
* pojos from 3rd party libraries.
*
* @author David Yu
*/
public final class RuntimeSchema implements Schema, FieldMap
{
public static final int MIN_TAG_VALUE = 1;
public static final int MAX_TAG_VALUE = 536870911; // 2^29 - 1
public static final String ERROR_TAG_VALUE = "Invalid tag number (value must be in range [1, 2^29-1])";
private static final Set NO_EXCLUSIONS = Collections.emptySet();
public static final int MIN_TAG_FOR_HASH_FIELD_MAP = 100;
private final Pipe.Schema pipeSchema;
private final FieldMap fieldMap;
private final Class typeClass;
/**
* Maps the {@code baseClass} to a specific non-interface/non-abstract {@code typeClass} and registers it (this must
* be done on application startup).
*
* With this approach, there is no overhead of writing the type metadata if a {@code baseClass} field is serialized.
*
* Returns true if the baseClass does not exist.
*
* NOTE: This is only supported when {@link RuntimeEnv#ID_STRATEGY} is {@link DefaultIdStrategy}.
*
* @throws IllegalArgumentException
* if the {@code typeClass} is an interface or an abstract class.
*/
public static boolean map(Class baseClass, Class typeClass)
{
if (ID_STRATEGY instanceof DefaultIdStrategy)
return ((DefaultIdStrategy) ID_STRATEGY).map(baseClass, typeClass);
throw new RuntimeException(
"RuntimeSchema.map is only supported on DefaultIdStrategy");
}
/**
* Returns true if this there is no existing one or the same schema has already been registered (this must be done
* on application startup).
*
* NOTE: This is only supported when {@link RuntimeEnv#ID_STRATEGY} is {@link DefaultIdStrategy}.
*/
public static boolean register(Class typeClass, Schema schema)
{
if (ID_STRATEGY instanceof DefaultIdStrategy)
return ((DefaultIdStrategy) ID_STRATEGY).registerPojo(typeClass,
schema);
throw new RuntimeException(
"RuntimeSchema.register is only supported on DefaultIdStrategy");
}
/**
* Returns true if this there is no existing one or the same schema has already been registered (this must be done
* on application startup).
*
* NOTE: This is only supported when {@link RuntimeEnv#ID_STRATEGY} is {@link DefaultIdStrategy}.
*/
public static boolean register(Class typeClass)
{
if (ID_STRATEGY instanceof DefaultIdStrategy)
return ((DefaultIdStrategy) ID_STRATEGY).registerPojo(typeClass);
throw new RuntimeException(
"RuntimeSchema.register is only supported on DefaultIdStrategy");
}
/**
* Returns true if the {@code typeClass} was not lazily created.
*
* Method overload for backwards compatibility.
*/
public static boolean isRegistered(Class typeClass)
{
return isRegistered(typeClass, ID_STRATEGY);
}
/**
* Returns true if the {@code typeClass} was not lazily created.
*/
public static boolean isRegistered(Class typeClass, IdStrategy strategy)
{
return strategy.isRegistered(typeClass);
}
/**
* Gets the schema that was either registered or lazily initialized at runtime.
*
* Method overload for backwards compatibility.
*/
public static Schema getSchema(Class typeClass)
{
return getSchema(typeClass, ID_STRATEGY);
}
/**
* Gets the schema that was either registered or lazily initialized at runtime.
*/
public static Schema getSchema(Class typeClass,
IdStrategy strategy)
{
return strategy.getSchemaWrapper(typeClass, true).getSchema();
}
/**
* Returns the schema wrapper.
*
* Method overload for backwards compatibility.
*/
static HasSchema getSchemaWrapper(Class typeClass)
{
return getSchemaWrapper(typeClass, ID_STRATEGY);
}
/**
* Returns the schema wrapper.
*/
static HasSchema getSchemaWrapper(Class typeClass,
IdStrategy strategy)
{
return strategy.getSchemaWrapper(typeClass, true);
}
/**
* Generates a schema from the given class.
*
* Method overload for backwards compatibility.
*/
public static RuntimeSchema createFrom(Class typeClass)
{
return createFrom(typeClass, NO_EXCLUSIONS, ID_STRATEGY);
}
/**
* Generates a schema from the given class.
*/
public static RuntimeSchema createFrom(Class typeClass,
IdStrategy strategy)
{
return createFrom(typeClass, NO_EXCLUSIONS, strategy);
}
/**
* Generates a schema from the given class with the exclusion of certain fields.
*/
public static RuntimeSchema createFrom(Class typeClass,
String[] exclusions, IdStrategy strategy)
{
HashSet set = new HashSet();
for (String exclusion : exclusions)
set.add(exclusion);
return createFrom(typeClass, set, strategy);
}
/**
* Generates a schema from the given class with the exclusion of certain fields.
*/
public static RuntimeSchema createFrom(Class typeClass,
Set exclusions, IdStrategy strategy)
{
if (typeClass.isInterface()
|| Modifier.isAbstract(typeClass.getModifiers()))
{
throw new RuntimeException(
"The root object can neither be an abstract "
+ "class nor interface: \"" + typeClass.getName());
}
final Map fieldMap = findInstanceFields(typeClass);
final ArrayList> fields = new ArrayList>(
fieldMap.size());
int i = 0;
boolean annotated = false;
for (java.lang.reflect.Field f : fieldMap.values())
{
if (!exclusions.contains(f.getName()))
{
if (f.getAnnotation(Deprecated.class) != null)
{
// this field should be ignored by ProtoStuff.
// preserve its field number for backward-forward compat
i++;
continue;
}
final Tag tag = f.getAnnotation(Tag.class);
final int fieldMapping;
final String name;
if (tag == null)
{
// Fields gets assigned mapping tags according to their
// definition order
if (annotated)
{
String className = typeClass.getCanonicalName();
String fieldName = f.getName();
String message = String.format("%s#%s is not annotated with @Tag", className, fieldName);
throw new RuntimeException(message);
}
fieldMapping = ++i;
name = f.getName();
}
else
{
// Fields gets assigned mapping tags according to their
// annotation
if (!annotated && !fields.isEmpty())
{
throw new RuntimeException(
"When using annotation-based mapping, "
+ "all fields must be annotated with @"
+ Tag.class.getSimpleName());
}
annotated = true;
fieldMapping = tag.value();
if (fieldMapping < MIN_TAG_VALUE || fieldMapping > MAX_TAG_VALUE)
{
throw new IllegalArgumentException(ERROR_TAG_VALUE + ": " + fieldMapping + " on " + typeClass);
}
name = tag.alias().isEmpty() ? f.getName() : tag.alias();
}
final Field field = RuntimeFieldFactory.getFieldFactory(
f.getType(), strategy).create(fieldMapping, name, f,
strategy);
fields.add(field);
}
}
return new RuntimeSchema(typeClass, fields,
RuntimeEnv.newInstantiator(typeClass));
}
/**
* Generates a schema from the given class with the declared fields (inclusive) based from the given Map. The value
* of a the Map's entry will be the name used for the field (which enables aliasing).
*/
public static RuntimeSchema createFrom(Class typeClass,
Map declaredFields, IdStrategy strategy)
{
if (typeClass.isInterface()
|| Modifier.isAbstract(typeClass.getModifiers()))
{
throw new RuntimeException(
"The root object can neither be an abstract "
+ "class nor interface: \"" + typeClass.getName());
}
final ArrayList> fields = new ArrayList>(
declaredFields.size());
int i = 0;
for (Map.Entry entry : declaredFields.entrySet())
{
final java.lang.reflect.Field f;
try
{
f = typeClass.getDeclaredField(entry.getKey());
}
catch (Exception e)
{
throw new IllegalArgumentException("Exception on field: "
+ entry.getKey(), e);
}
final int mod = f.getModifiers();
if (!Modifier.isStatic(mod) && !Modifier.isTransient(mod) && f.getAnnotation(Exclude.class) == null)
{
final Field field = RuntimeFieldFactory.getFieldFactory(
f.getType(), strategy).create(++i, entry.getValue(), f,
strategy);
fields.add(field);
}
}
return new RuntimeSchema(typeClass, fields, RuntimeEnv.newInstantiator(typeClass));
}
static Map findInstanceFields(
Class typeClass)
{
LinkedHashMap fieldMap = new LinkedHashMap();
fill(fieldMap, typeClass);
return fieldMap;
}
static void fill(Map fieldMap,
Class typeClass)
{
if (Object.class != typeClass.getSuperclass())
fill(fieldMap, typeClass.getSuperclass());
for (java.lang.reflect.Field f : typeClass.getDeclaredFields())
{
int mod = f.getModifiers();
if (!Modifier.isStatic(mod) && !Modifier.isTransient(mod) && f.getAnnotation(Exclude.class) == null)
fieldMap.put(f.getName(), f);
}
}
public final Instantiator instantiator;
public RuntimeSchema(Class typeClass, Collection> fields, Constructor constructor)
{
this(typeClass, fields, new DefaultInstantiator(
constructor));
}
public RuntimeSchema(Class typeClass, Collection> fields, Instantiator instantiator)
{
this.fieldMap = createFieldMap(fields);
this.pipeSchema = new RuntimePipeSchema(this, fieldMap);
this.instantiator = instantiator;
this.typeClass = typeClass;
}
private FieldMap createFieldMap(Collection> fields)
{
int lastFieldNumber = 0;
for (Field field : fields)
{
if (field.number > lastFieldNumber)
{
lastFieldNumber = field.number;
}
}
if (preferHashFieldMap(fields, lastFieldNumber))
{
return new HashFieldMap(fields);
}
// array field map should be more efficient
return new ArrayFieldMap(fields, lastFieldNumber);
}
private boolean preferHashFieldMap(Collection> fields, int lastFieldNumber)
{
return lastFieldNumber > MIN_TAG_FOR_HASH_FIELD_MAP && lastFieldNumber >= 2 * fields.size();
}
/**
* Returns the pipe schema linked to this.
*/
public Pipe.Schema getPipeSchema()
{
return pipeSchema;
}
@Override
public Field getFieldByNumber(int n)
{
return fieldMap.getFieldByNumber(n);
}
@Override
public Field getFieldByName(String fieldName)
{
return fieldMap.getFieldByName(fieldName);
}
@Override
public int getFieldCount()
{
return fieldMap.getFieldCount();
}
@Override
public List> getFields()
{
return fieldMap.getFields();
}
@Override
public Class typeClass()
{
return typeClass;
}
@Override
public String messageName()
{
return typeClass.getSimpleName();
}
@Override
public String messageFullName()
{
return typeClass.getName();
}
@Override
public String getFieldName(int number)
{
// only called on writes
final Field field = getFieldByNumber(number);
return field == null ? null : field.name;
}
@Override
public int getFieldNumber(String name)
{
final Field field = getFieldByName(name);
return field == null ? 0 : field.number;
}
@Override
public final void mergeFrom(Input input, T message) throws IOException
{
for (int n = input.readFieldNumber(this); n != 0; n = input.readFieldNumber(this))
{
final Field field = getFieldByNumber(n);
if (field == null)
{
input.handleUnknownField(n, this);
}
else
{
field.mergeFrom(input, message);
}
}
}
@Override
public final void writeTo(Output output, T message) throws IOException
{
for (Field f : getFields())
f.writeTo(output, message);
}
/**
* Always returns true, everything is optional.
*/
@Override
public boolean isInitialized(T message)
{
return true;
}
@Override
public T newMessage()
{
return instantiator.newInstance();
}
/**
* Invoked only when applications are having pipe io operations.
*/
@SuppressWarnings("unchecked")
static Pipe.Schema resolvePipeSchema(Schema schema,
Class clazz, boolean throwIfNone)
{
if (Message.class.isAssignableFrom(clazz))
{
try
{
// use the pipe schema of code-generated messages if available.
java.lang.reflect.Method m = clazz.getDeclaredMethod("getPipeSchema");
return (Pipe.Schema) m.invoke(null);
}
catch (Exception e)
{
// ignore
}
}
if (RuntimeSchema.class.isAssignableFrom(schema.getClass()))
return ((RuntimeSchema) schema).getPipeSchema();
if (throwIfNone)
throw new RuntimeException("No pipe schema for: " + clazz);
return null;
}
}