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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* 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 java.io;
/**
* An EmulatedFields is an object that represents a set of emulated fields for
* an object being dumped or loaded. It allows objects to be dumped with a shape
* different than the fields they were declared to have.
*
* @see ObjectInputStream.GetField
* @see ObjectOutputStream.PutField
* @see EmulatedFieldsForLoading
* @see EmulatedFieldsForDumping
*/
class EmulatedFields {
// A slot is a field plus its value
static class ObjectSlot {
// Field descriptor
ObjectStreamField field;
// Actual value this emulated field holds
Object fieldValue;
// If this field has a default value (true) or something has been
// assigned (false)
boolean defaulted = true;
/**
* Returns the descriptor for this emulated field.
*
* @return the field descriptor
*/
public ObjectStreamField getField() {
return field;
}
/**
* Returns the value held by this emulated field.
*
* @return the field value
*/
public Object getFieldValue() {
return fieldValue;
}
}
// The collection of slots the receiver represents
private ObjectSlot[] slotsToSerialize;
private ObjectStreamField[] declaredFields;
/**
* Constructs a new instance of EmulatedFields.
*
* @param fields
* an array of ObjectStreamFields, which describe the fields to
* be emulated (names, types, etc).
* @param declared
* an array of ObjectStreamFields, which describe the declared
* fields.
*/
public EmulatedFields(ObjectStreamField[] fields, ObjectStreamField[] declared) {
// We assume the slots are already sorted in the right shape for dumping
buildSlots(fields);
declaredFields = declared;
}
/**
* Build emulated slots that correspond to emulated fields. A slot is a
* field descriptor (ObjectStreamField) plus the actual value it holds.
*
* @param fields
* an array of ObjectStreamField, which describe the fields to be
* emulated (names, types, etc).
*/
private void buildSlots(ObjectStreamField[] fields) {
slotsToSerialize = new ObjectSlot[fields.length];
for (int i = 0; i < fields.length; i++) {
ObjectSlot s = new ObjectSlot();
slotsToSerialize[i] = s;
s.field = fields[i];
}
// We assume the slots are already sorted in the right shape for dumping
}
/**
* Returns {@code true} indicating the field called {@code name} has not had
* a value explicitly assigned and that it still holds a default value for
* its type, or {@code false} indicating that the field named has been
* assigned a value explicitly.
*
* @param name
* the name of the field to test.
* @return {@code true} if {@code name} still holds its default value,
* {@code false} otherwise
*
* @throws IllegalArgumentException
* if {@code name} is {@code null}
*/
public boolean defaulted(String name) throws IllegalArgumentException {
ObjectSlot slot = findSlot(name, null);
if (slot == null) {
throw new IllegalArgumentException("no field '" + name + "'");
}
return slot.defaulted;
}
/**
* Finds and returns an ObjectSlot that corresponds to a field named {@code
* fieldName} and type {@code fieldType}. If the field type {@code
* fieldType} corresponds to a primitive type, the field type has to match
* exactly or {@code null} is returned. If the field type {@code fieldType}
* corresponds to an object type, the field type has to be compatible in
* terms of assignment, or null is returned. If {@code fieldType} is {@code
* null}, no such compatibility checking is performed and the slot is
* returned.
*
* @param fieldName
* the name of the field to find
* @param fieldType
* the type of the field. This will be used to test
* compatibility. If {@code null}, no testing is done, the
* corresponding slot is returned.
* @return the object slot, or {@code null} if there is no field with that
* name, or no compatible field (relative to {@code fieldType})
*/
private ObjectSlot findSlot(String fieldName, Class fieldType) {
boolean isPrimitive = fieldType != null && fieldType.isPrimitive();
for (int i = 0; i < slotsToSerialize.length; i++) {
ObjectSlot slot = slotsToSerialize[i];
if (slot.field.getName().equals(fieldName)) {
if (isPrimitive) {
// Looking for a primitive type field. Types must match
// *exactly*
if (slot.field.getType() == fieldType) {
return slot;
}
} else {
// Looking for a non-primitive type field.
if (fieldType == null) {
return slot; // Null means we take anything
}
// Types must be compatible (assignment)
if (slot.field.getType().isAssignableFrom(fieldType)) {
return slot;
}
}
}
}
if (declaredFields != null) {
for (int i = 0; i < declaredFields.length; i++) {
ObjectStreamField field = declaredFields[i];
if (field.getName().equals(fieldName)) {
if (isPrimitive ? fieldType == field.getType() : fieldType == null ||
field.getType().isAssignableFrom(fieldType)) {
ObjectSlot slot = new ObjectSlot();
slot.field = field;
slot.defaulted = true;
return slot;
}
}
}
}
return null;
}
private ObjectSlot findMandatorySlot(String name, Class type) {
ObjectSlot slot = findSlot(name, type);
if (slot == null || (type == null && slot.field.getType().isPrimitive())) {
throw new IllegalArgumentException("no field '" + name + "' of type " + type);
}
return slot;
}
/**
* Finds and returns the byte value of a given field named {@code name}
* in the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public byte get(String name, byte defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, byte.class);
return slot.defaulted ? defaultValue : ((Byte) slot.fieldValue).byteValue();
}
/**
* Finds and returns the char value of a given field named {@code name} in the
* receiver. If the field has not been assigned any value yet, the default
* value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public char get(String name, char defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, char.class);
return slot.defaulted ? defaultValue : ((Character) slot.fieldValue).charValue();
}
/**
* Finds and returns the double value of a given field named {@code name}
* in the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public double get(String name, double defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, double.class);
return slot.defaulted ? defaultValue : ((Double) slot.fieldValue).doubleValue();
}
/**
* Finds and returns the float value of a given field named {@code name} in
* the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public float get(String name, float defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, float.class);
return slot.defaulted ? defaultValue : ((Float) slot.fieldValue).floatValue();
}
/**
* Finds and returns the int value of a given field named {@code name} in the
* receiver. If the field has not been assigned any value yet, the default
* value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public int get(String name, int defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, int.class);
return slot.defaulted ? defaultValue : ((Integer) slot.fieldValue).intValue();
}
/**
* Finds and returns the long value of a given field named {@code name} in the
* receiver. If the field has not been assigned any value yet, the default
* value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public long get(String name, long defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, long.class);
return slot.defaulted ? defaultValue : ((Long) slot.fieldValue).longValue();
}
/**
* Finds and returns the Object value of a given field named {@code name} in
* the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public Object get(String name, Object defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, null);
return slot.defaulted ? defaultValue : slot.fieldValue;
}
/**
* Finds and returns the short value of a given field named {@code name} in
* the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public short get(String name, short defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, short.class);
return slot.defaulted ? defaultValue : ((Short) slot.fieldValue).shortValue();
}
/**
* Finds and returns the boolean value of a given field named {@code name} in
* the receiver. If the field has not been assigned any value yet, the
* default value {@code defaultValue} is returned instead.
*
* @param name
* the name of the field to find.
* @param defaultValue
* return value in case the field has not been assigned to yet.
* @return the value of the given field if it has been assigned, the default
* value otherwise.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public boolean get(String name, boolean defaultValue) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, boolean.class);
return slot.defaulted ? defaultValue : ((Boolean) slot.fieldValue).booleanValue();
}
/**
* Find and set the byte value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, byte value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, byte.class);
slot.fieldValue = Byte.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the char value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, char value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, char.class);
slot.fieldValue = Character.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the double value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, double value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, double.class);
slot.fieldValue = Double.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the float value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, float value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, float.class);
slot.fieldValue = Float.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the int value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, int value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, int.class);
slot.fieldValue = Integer.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the long value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, long value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, long.class);
slot.fieldValue = Long.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the Object value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, Object value) throws IllegalArgumentException {
Class valueClass = null;
if (value != null) {
valueClass = value.getClass();
}
ObjectSlot slot = findMandatorySlot(name, valueClass);
slot.fieldValue = value;
slot.defaulted = false; // No longer default value
}
/**
* Find and set the short value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, short value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, short.class);
slot.fieldValue = Short.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Find and set the boolean value of a given field named {@code name} in the
* receiver.
*
* @param name
* the name of the field to set.
* @param value
* new value for the field.
*
* @throws IllegalArgumentException
* if the corresponding field can not be found.
*/
public void put(String name, boolean value) throws IllegalArgumentException {
ObjectSlot slot = findMandatorySlot(name, boolean.class);
slot.fieldValue = Boolean.valueOf(value);
slot.defaulted = false; // No longer default value
}
/**
* Return the array of ObjectSlot the receiver represents.
*
* @return array of ObjectSlot the receiver represents.
*/
public ObjectSlot[] slots() {
return slotsToSerialize;
}
}