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// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This file specifies a recursive data storage class called Value intended for
// storing settings and other persistable data.
//
// A Value represents something that can be stored in JSON or passed to/from
// JavaScript. As such, it is NOT a generalized variant type, since only the
// types supported by JavaScript/JSON are supported.
//
// IN PARTICULAR this means that there is no support for int64_t or unsigned
// numbers. Writing JSON with such types would violate the spec. If you need
// something like this, either use a double or make a string value containing
// the number you want.
//
// NOTE: A Value parameter that is always a Value::STRING should just be passed
// as a std::string. Similarly for Values that are always Value::DICTIONARY
// (should be flat_map), Value::LIST (should be std::vector), et cetera.
#ifndef BASE_VALUES_H_
#define BASE_VALUES_H_
#include <iosfwd>
#include <map>
#include <memory>
#include <string>
#include <utility>
#include <vector>
#include "base/base_export.h"
#include "base/containers/flat_map.h"
#include "base/containers/span.h"
#include "base/macros.h"
#include "base/strings/string16.h"
#include "base/strings/string_piece.h"
#include "base/value_iterators.h"
#include "starboard/types.h"
namespace base {
class DictionaryValue;
class ListValue;
class Value;
// The Value class is the base class for Values. A Value can be instantiated
// via passing the appropriate type or backing storage to the constructor.
//
// See the file-level comment above for more information.
//
// base::Value is currently in the process of being refactored. Design doc:
// https://docs.google.com/document/d/1uDLu5uTRlCWePxQUEHc8yNQdEoE1BDISYdpggWEABnw
//
// Previously (which is how most code that currently exists is written), Value
// used derived types to implement the individual data types, and base::Value
// was just a base class to refer to them. This required everything be heap
// allocated.
//
// OLD WAY:
//
// std::unique_ptr<base::Value> GetFoo() {
// std::unique_ptr<DictionaryValue> dict;
// dict->SetString("mykey", foo);
// return dict;
// }
//
// The new design makes base::Value a variant type that holds everything in
// a union. It is now recommended to pass by value with std::move rather than
// use heap allocated values. The DictionaryValue and ListValue subclasses
// exist only as a compatibility shim that we're in the process of removing.
//
// NEW WAY:
//
// base::Value GetFoo() {
// base::Value dict(base::Value::Type::DICTIONARY);
// dict.SetKey("mykey", base::Value(foo));
// return dict;
// }
class BASE_EXPORT Value {
public:
using BlobStorage = std::vector<uint8_t>;
using DictStorage = flat_map<std::string, std::unique_ptr<Value>>;
using ListStorage = std::vector<Value>;
enum class Type {
NONE = 0,
BOOLEAN,
INTEGER,
DOUBLE,
STRING,
BINARY,
DICTIONARY,
LIST
// Note: Do not add more types. See the file-level comment above for why.
};
// Magic IsAlive signature to debug double frees.
// TODO(crbug.com/859477): Remove once root cause is found.
static constexpr uint32_t kMagicIsAlive = 0x15272f19;
// For situations where you want to keep ownership of your buffer, this
// factory method creates a new BinaryValue by copying the contents of the
// buffer that's passed in.
// DEPRECATED, use std::make_unique<Value>(const BlobStorage&) instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
static std::unique_ptr<Value> CreateWithCopiedBuffer(const char* buffer,
size_t size);
// Adaptors for converting from the old way to the new way and vice versa.
static Value FromUniquePtrValue(std::unique_ptr<Value> val);
static std::unique_ptr<Value> ToUniquePtrValue(Value val);
Value(Value&& that) noexcept;
Value() noexcept; // A null value.
// Value's copy constructor and copy assignment operator are deleted. Use this
// to obtain a deep copy explicitly.
Value Clone() const;
explicit Value(Type type);
explicit Value(bool in_bool);
explicit Value(int in_int);
explicit Value(double in_double);
// Value(const char*) and Value(const char16*) are required despite
// Value(StringPiece) and Value(StringPiece16) because otherwise the
// compiler will choose the Value(bool) constructor for these arguments.
// Value(std::string&&) allow for efficient move construction.
explicit Value(const char* in_string);
explicit Value(StringPiece in_string);
explicit Value(std::string&& in_string) noexcept;
explicit Value(const char16* in_string16);
explicit Value(StringPiece16 in_string16);
#if defined(STARBOARD) && SB_IS(COMPILER_MSVC)
explicit Value(const std::string& in_string) : Value(in_string.c_str()) {}
#endif
explicit Value(const std::vector<char>& in_blob);
explicit Value(base::span<const uint8_t> in_blob);
#if defined(STARBOARD) && SB_IS(COMPILER_MSVC)
Value::Value(const BlobStorage& in_blob);
#endif
explicit Value(BlobStorage&& in_blob) noexcept;
explicit Value(const DictStorage& in_dict);
explicit Value(DictStorage&& in_dict) noexcept;
explicit Value(const ListStorage& in_list);
explicit Value(ListStorage&& in_list) noexcept;
Value& operator=(Value&& that) noexcept;
~Value();
// Returns the name for a given |type|.
static const char* GetTypeName(Type type);
// Returns the type of the value stored by the current Value object.
Type type() const { return type_; }
// Returns true if the current object represents a given type.
bool is_none() const { return type() == Type::NONE; }
bool is_bool() const { return type() == Type::BOOLEAN; }
bool is_int() const { return type() == Type::INTEGER; }
bool is_double() const { return type() == Type::DOUBLE; }
bool is_string() const { return type() == Type::STRING; }
bool is_blob() const { return type() == Type::BINARY; }
bool is_dict() const { return type() == Type::DICTIONARY; }
bool is_list() const { return type() == Type::LIST; }
// These will all fatally assert if the type doesn't match.
bool GetBool() const;
int GetInt() const;
double GetDouble() const; // Implicitly converts from int if necessary.
const std::string& GetString() const;
const BlobStorage& GetBlob() const;
ListStorage& GetList();
const ListStorage& GetList() const;
// Transfers ownership of the underlying list to the caller. Subsequent
// calls to `GetList()` will return an empty list.
// Note: This requires that `type()` is Type::LIST.
ListStorage TakeList();
// |FindKey| looks up |key| in the underlying dictionary. If found, it returns
// a pointer to the element. Otherwise it returns nullptr.
// returned. Callers are expected to perform a check against null before using
// the pointer.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
//
// Example:
// auto* found = FindKey("foo");
Value* FindKey(StringPiece key);
const Value* FindKey(StringPiece key) const;
// |FindKeyOfType| is similar to |FindKey|, but it also requires the found
// value to have type |type|. If no type is found, or the found value is of a
// different type nullptr is returned.
// Callers are expected to perform a check against null before using the
// pointer.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
//
// Example:
// auto* found = FindKey("foo", Type::DOUBLE);
Value* FindKeyOfType(StringPiece key, Type type);
const Value* FindKeyOfType(StringPiece key, Type type) const;
// |SetKey| looks up |key| in the underlying dictionary and sets the mapped
// value to |value|. If |key| could not be found, a new element is inserted.
// A pointer to the modified item is returned.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
//
// Example:
// SetKey("foo", std::move(myvalue));
Value* SetKey(StringPiece key, Value value);
// This overload results in a performance improvement for std::string&&.
Value* SetKey(std::string&& key, Value value);
// This overload is necessary to avoid ambiguity for const char* arguments.
Value* SetKey(const char* key, Value value);
// This attemps to remove the value associated with |key|. In case of failure,
// e.g. the key does not exist, |false| is returned and the underlying
// dictionary is not changed. In case of success, |key| is deleted from the
// dictionary and the method returns |true|.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
//
// Example:
// bool success = RemoveKey("foo");
bool RemoveKey(StringPiece key);
// Searches a hierarchy of dictionary values for a given value. If a path
// of dictionaries exist, returns the item at that path. If any of the path
// components do not exist or if any but the last path components are not
// dictionaries, returns nullptr.
//
// The type of the leaf Value is not checked.
//
// Implementation note: This can't return an iterator because the iterator
// will actually be into another Value, so it can't be compared to iterators
// from this one (in particular, the DictItems().end() iterator).
//
// Example:
// auto* found = FindPath({"foo", "bar"});
//
// std::vector<StringPiece> components = ...
// auto* found = FindPath(components);
//
// Note: If there is only one component in the path, use FindKey() instead.
Value* FindPath(std::initializer_list<StringPiece> path);
Value* FindPath(span<const StringPiece> path);
#if defined(STARBOARD)
// This is a bandage on the inability to implicitly convert to span.
Value* FindPath(const std::vector<StringPiece>& path) {
return FindPath(span<const StringPiece>(path.data(), path.size()));
}
#endif
const Value* FindPath(std::initializer_list<StringPiece> path) const;
const Value* FindPath(span<const StringPiece> path) const;
// Like FindPath() but will only return the value if the leaf Value type
// matches the given type. Will return nullptr otherwise.
//
// Note: If there is only one component in the path, use FindKeyOfType()
// instead.
Value* FindPathOfType(std::initializer_list<StringPiece> path, Type type);
Value* FindPathOfType(span<const StringPiece> path, Type type);
const Value* FindPathOfType(std::initializer_list<StringPiece> path,
Type type) const;
const Value* FindPathOfType(span<const StringPiece> path, Type type) const;
// Sets the given path, expanding and creating dictionary keys as necessary.
//
// If the current value is not a dictionary, the function returns nullptr. If
// path components do not exist, they will be created. If any but the last
// components matches a value that is not a dictionary, the function will fail
// (it will not overwrite the value) and return nullptr. The last path
// component will be unconditionally overwritten if it exists, and created if
// it doesn't.
//
// Example:
// value.SetPath({"foo", "bar"}, std::move(myvalue));
//
// std::vector<StringPiece> components = ...
// value.SetPath(components, std::move(myvalue));
//
// Note: If there is only one component in the path, use SetKey() instead.
Value* SetPath(std::initializer_list<StringPiece> path, Value value);
Value* SetPath(span<const StringPiece> path, Value value);
// Tries to remove a Value at the given path.
//
// If the current value is not a dictionary or any path components does not
// exist, this operation fails, leaves underlying Values untouched and returns
// |false|. In case intermediate dictionaries become empty as a result of this
// path removal, they will be removed as well.
//
// Example:
// bool success = value.RemovePath({"foo", "bar"});
//
// std::vector<StringPiece> components = ...
// bool success = value.RemovePath(components);
//
// Note: If there is only one component in the path, use RemoveKey() instead.
bool RemovePath(std::initializer_list<StringPiece> path);
bool RemovePath(span<const StringPiece> path);
using dict_iterator_proxy = detail::dict_iterator_proxy;
using const_dict_iterator_proxy = detail::const_dict_iterator_proxy;
// |DictItems| returns a proxy object that exposes iterators to the underlying
// dictionary. These are intended for iteration over all items in the
// dictionary and are compatible with for-each loops and standard library
// algorithms.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
dict_iterator_proxy DictItems();
const_dict_iterator_proxy DictItems() const;
// Returns the size of the dictionary, and if the dictionary is empty.
// Note: This fatally asserts if type() is not Type::DICTIONARY.
size_t DictSize() const;
bool DictEmpty() const;
// Merge |dictionary| into this value. This is done recursively, i.e. any
// sub-dictionaries will be merged as well. In case of key collisions, the
// passed in dictionary takes precedence and data already present will be
// replaced. Values within |dictionary| are deep-copied, so |dictionary| may
// be freed any time after this call.
// Note: This fatally asserts if type() or dictionary->type() is not
// Type::DICTIONARY.
void MergeDictionary(const Value* dictionary);
// These methods allow the convenient retrieval of the contents of the Value.
// If the current object can be converted into the given type, the value is
// returned through the |out_value| parameter and true is returned;
// otherwise, false is returned and |out_value| is unchanged.
// DEPRECATED, use GetBool() instead.
bool GetAsBoolean(bool* out_value) const;
// DEPRECATED, use GetInt() instead.
bool GetAsInteger(int* out_value) const;
// DEPRECATED, use GetDouble() instead.
bool GetAsDouble(double* out_value) const;
// DEPRECATED, use GetString() instead.
bool GetAsString(std::string* out_value) const;
bool GetAsString(string16* out_value) const;
bool GetAsString(const Value** out_value) const;
bool GetAsString(StringPiece* out_value) const;
// ListValue::From is the equivalent for std::unique_ptr conversions.
// DEPRECATED, use GetList() instead.
bool GetAsList(ListValue** out_value);
bool GetAsList(const ListValue** out_value) const;
// DictionaryValue::From is the equivalent for std::unique_ptr conversions.
bool GetAsDictionary(DictionaryValue** out_value);
bool GetAsDictionary(const DictionaryValue** out_value) const;
// Note: Do not add more types. See the file-level comment above for why.
// This creates a deep copy of the entire Value tree, and returns a pointer
// to the copy. The caller gets ownership of the copy, of course.
// Subclasses return their own type directly in their overrides;
// this works because C++ supports covariant return types.
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
Value* DeepCopy() const;
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
std::unique_ptr<Value> CreateDeepCopy() const;
// Comparison operators so that Values can easily be used with standard
// library algorithms and associative containers.
BASE_EXPORT friend bool operator==(const Value& lhs, const Value& rhs);
BASE_EXPORT friend bool operator!=(const Value& lhs, const Value& rhs);
BASE_EXPORT friend bool operator<(const Value& lhs, const Value& rhs);
BASE_EXPORT friend bool operator>(const Value& lhs, const Value& rhs);
BASE_EXPORT friend bool operator<=(const Value& lhs, const Value& rhs);
BASE_EXPORT friend bool operator>=(const Value& lhs, const Value& rhs);
// Compares if two Value objects have equal contents.
// DEPRECATED, use operator==(const Value& lhs, const Value& rhs) instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
bool Equals(const Value* other) const;
// Estimates dynamic memory usage.
// See base/trace_event/memory_usage_estimator.h for more info.
size_t EstimateMemoryUsage() const;
protected:
// TODO(crbug.com/646113): Make these private once DictionaryValue and
// ListValue are properly inlined.
Type type_;
union {
bool bool_value_;
int int_value_;
double double_value_;
std::string string_value_;
BlobStorage binary_value_;
DictStorage dict_;
ListStorage list_;
};
private:
void InternalMoveConstructFrom(Value&& that);
void InternalCleanup();
// IsAlive member to debug double frees.
// TODO(crbug.com/859477): Remove once root cause is found.
uint32_t is_alive_ = kMagicIsAlive;
DISALLOW_COPY_AND_ASSIGN(Value);
};
// DictionaryValue provides a key-value dictionary with (optional) "path"
// parsing for recursive access; see the comment at the top of the file. Keys
// are |std::string|s and should be UTF-8 encoded.
class BASE_EXPORT DictionaryValue : public Value {
public:
using const_iterator = DictStorage::const_iterator;
using iterator = DictStorage::iterator;
// Returns |value| if it is a dictionary, nullptr otherwise.
static std::unique_ptr<DictionaryValue> From(std::unique_ptr<Value> value);
DictionaryValue();
explicit DictionaryValue(const DictStorage& in_dict);
explicit DictionaryValue(DictStorage&& in_dict) noexcept;
// Returns true if the current dictionary has a value for the given key.
// DEPRECATED, use Value::FindKey(key) instead.
bool HasKey(StringPiece key) const;
// Returns the number of Values in this dictionary.
size_t size() const { return dict_.size(); }
// Returns whether the dictionary is empty.
bool empty() const { return dict_.empty(); }
// Clears any current contents of this dictionary.
void Clear();
// Sets the Value associated with the given path starting from this object.
// A path has the form "<key>" or "<key>.<key>.[...]", where "." indexes
// into the next DictionaryValue down. Obviously, "." can't be used
// within a key, but there are no other restrictions on keys.
// If the key at any step of the way doesn't exist, or exists but isn't
// a DictionaryValue, a new DictionaryValue will be created and attached
// to the path in that location. |in_value| must be non-null.
// Returns a pointer to the inserted value.
// DEPRECATED, use Value::SetPath(path, value) instead.
Value* Set(StringPiece path, std::unique_ptr<Value> in_value);
// Convenience forms of Set(). These methods will replace any existing
// value at that path, even if it has a different type.
// DEPRECATED, use Value::SetPath(path, Value(bool)) instead.
Value* SetBoolean(StringPiece path, bool in_value);
// DEPRECATED, use Value::SetPath(path, Value(int)) instead.
Value* SetInteger(StringPiece path, int in_value);
// DEPRECATED, use Value::SetPath(path, Value(double)) instead.
Value* SetDouble(StringPiece path, double in_value);
// DEPRECATED, use Value::SetPath(path, Value(StringPiece)) instead.
Value* SetString(StringPiece path, StringPiece in_value);
// DEPRECATED, use Value::SetPath(path, Value(const string& 16)) instead.
Value* SetString(StringPiece path, const string16& in_value);
// DEPRECATED, use Value::SetPath(path, Value(Type::DICTIONARY)) instead.
DictionaryValue* SetDictionary(StringPiece path,
std::unique_ptr<DictionaryValue> in_value);
// DEPRECATED, use Value::SetPath(path, Value(Type::LIST)) instead.
ListValue* SetList(StringPiece path, std::unique_ptr<ListValue> in_value);
// Like Set(), but without special treatment of '.'. This allows e.g. URLs to
// be used as paths.
// DEPRECATED, use Value::SetKey(key, value) instead.
Value* SetWithoutPathExpansion(StringPiece key,
std::unique_ptr<Value> in_value);
// Gets the Value associated with the given path starting from this object.
// A path has the form "<key>" or "<key>.<key>.[...]", where "." indexes
// into the next DictionaryValue down. If the path can be resolved
// successfully, the value for the last key in the path will be returned
// through the |out_value| parameter, and the function will return true.
// Otherwise, it will return false and |out_value| will be untouched.
// Note that the dictionary always owns the value that's returned.
// |out_value| is optional and will only be set if non-NULL.
// DEPRECATED, use Value::FindPath(path) instead.
bool Get(StringPiece path, const Value** out_value) const;
// DEPRECATED, use Value::FindPath(path) instead.
bool Get(StringPiece path, Value** out_value);
// These are convenience forms of Get(). The value will be retrieved
// and the return value will be true if the path is valid and the value at
// the end of the path can be returned in the form specified.
// |out_value| is optional and will only be set if non-NULL.
// DEPRECATED, use Value::FindPath(path) and Value::GetBool() instead.
bool GetBoolean(StringPiece path, bool* out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetInt() instead.
bool GetInteger(StringPiece path, int* out_value) const;
// Values of both type Type::INTEGER and Type::DOUBLE can be obtained as
// doubles.
// DEPRECATED, use Value::FindPath(path) and Value::GetDouble() instead.
bool GetDouble(StringPiece path, double* out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetString() instead.
bool GetString(StringPiece path, std::string* out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetString() instead.
bool GetString(StringPiece path, string16* out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetString() instead.
bool GetStringASCII(StringPiece path, std::string* out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetBlob() instead.
bool GetBinary(StringPiece path, const Value** out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetBlob() instead.
bool GetBinary(StringPiece path, Value** out_value);
// DEPRECATED, use Value::FindPath(path) and Value's Dictionary API instead.
bool GetDictionary(StringPiece path,
const DictionaryValue** out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value's Dictionary API instead.
bool GetDictionary(StringPiece path, DictionaryValue** out_value);
// DEPRECATED, use Value::FindPath(path) and Value::GetList() instead.
bool GetList(StringPiece path, const ListValue** out_value) const;
// DEPRECATED, use Value::FindPath(path) and Value::GetList() instead.
bool GetList(StringPiece path, ListValue** out_value);
// Like Get(), but without special treatment of '.'. This allows e.g. URLs to
// be used as paths.
// DEPRECATED, use Value::FindKey(key) instead.
bool GetWithoutPathExpansion(StringPiece key, const Value** out_value) const;
// DEPRECATED, use Value::FindKey(key) instead.
bool GetWithoutPathExpansion(StringPiece key, Value** out_value);
// DEPRECATED, use Value::FindKey(key) and Value::GetBool() instead.
bool GetBooleanWithoutPathExpansion(StringPiece key, bool* out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value::GetInt() instead.
bool GetIntegerWithoutPathExpansion(StringPiece key, int* out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value::GetDouble() instead.
bool GetDoubleWithoutPathExpansion(StringPiece key, double* out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value::GetString() instead.
bool GetStringWithoutPathExpansion(StringPiece key,
std::string* out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value::GetString() instead.
bool GetStringWithoutPathExpansion(StringPiece key,
string16* out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value's Dictionary API instead.
bool GetDictionaryWithoutPathExpansion(
StringPiece key,
const DictionaryValue** out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value's Dictionary API instead.
bool GetDictionaryWithoutPathExpansion(StringPiece key,
DictionaryValue** out_value);
// DEPRECATED, use Value::FindKey(key) and Value::GetList() instead.
bool GetListWithoutPathExpansion(StringPiece key,
const ListValue** out_value) const;
// DEPRECATED, use Value::FindKey(key) and Value::GetList() instead.
bool GetListWithoutPathExpansion(StringPiece key, ListValue** out_value);
// Removes the Value with the specified path from this dictionary (or one
// of its child dictionaries, if the path is more than just a local key).
// If |out_value| is non-NULL, the removed Value will be passed out via
// |out_value|. If |out_value| is NULL, the removed value will be deleted.
// This method returns true if |path| is a valid path; otherwise it will
// return false and the DictionaryValue object will be unchanged.
// DEPRECATED, use Value::RemovePath(path) instead.
bool Remove(StringPiece path, std::unique_ptr<Value>* out_value);
// Like Remove(), but without special treatment of '.'. This allows e.g. URLs
// to be used as paths.
// DEPRECATED, use Value::RemoveKey(key) instead.
bool RemoveWithoutPathExpansion(StringPiece key,
std::unique_ptr<Value>* out_value);
// Removes a path, clearing out all dictionaries on |path| that remain empty
// after removing the value at |path|.
// DEPRECATED, use Value::RemovePath(path) instead.
bool RemovePath(StringPiece path, std::unique_ptr<Value>* out_value);
using Value::RemovePath; // DictionaryValue::RemovePath shadows otherwise.
// Makes a copy of |this| but doesn't include empty dictionaries and lists in
// the copy. This never returns NULL, even if |this| itself is empty.
std::unique_ptr<DictionaryValue> DeepCopyWithoutEmptyChildren() const;
// Swaps contents with the |other| dictionary.
void Swap(DictionaryValue* other);
// This class provides an iterator over both keys and values in the
// dictionary. It can't be used to modify the dictionary.
// DEPRECATED, use Value::DictItems() instead.
class BASE_EXPORT Iterator {
public:
explicit Iterator(const DictionaryValue& target);
Iterator(const Iterator& other);
~Iterator();
bool IsAtEnd() const { return it_ == target_.dict_.end(); }
void Advance() { ++it_; }
const std::string& key() const { return it_->first; }
const Value& value() const { return *it_->second; }
private:
const DictionaryValue& target_;
DictStorage::const_iterator it_;
};
// Iteration.
// DEPRECATED, use Value::DictItems() instead.
iterator begin() { return dict_.begin(); }
iterator end() { return dict_.end(); }
// DEPRECATED, use Value::DictItems() instead.
const_iterator begin() const { return dict_.begin(); }
const_iterator end() const { return dict_.end(); }
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
DictionaryValue* DeepCopy() const;
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
std::unique_ptr<DictionaryValue> CreateDeepCopy() const;
};
// This type of Value represents a list of other Value values.
class BASE_EXPORT ListValue : public Value {
public:
using const_iterator = ListStorage::const_iterator;
using iterator = ListStorage::iterator;
// Returns |value| if it is a list, nullptr otherwise.
static std::unique_ptr<ListValue> From(std::unique_ptr<Value> value);
ListValue();
explicit ListValue(const ListStorage& in_list);
explicit ListValue(ListStorage&& in_list) noexcept;
// Clears the contents of this ListValue
// DEPRECATED, use GetList()::clear() instead.
void Clear();
// Returns the number of Values in this list.
// DEPRECATED, use GetList()::size() instead.
size_t GetSize() const { return list_.size(); }
// Returns whether the list is empty.
// DEPRECATED, use GetList()::empty() instead.
bool empty() const { return list_.empty(); }
// Reserves storage for at least |n| values.
// DEPRECATED, use GetList()::reserve() instead.
void Reserve(size_t n);
// Sets the list item at the given index to be the Value specified by
// the value given. If the index beyond the current end of the list, null
// Values will be used to pad out the list.
// Returns true if successful, or false if the index was negative or
// the value is a null pointer.
// DEPRECATED, use GetList()::operator[] instead.
bool Set(size_t index, std::unique_ptr<Value> in_value);
// Gets the Value at the given index. Modifies |out_value| (and returns true)
// only if the index falls within the current list range.
// Note that the list always owns the Value passed out via |out_value|.
// |out_value| is optional and will only be set if non-NULL.
// DEPRECATED, use GetList()::operator[] instead.
bool Get(size_t index, const Value** out_value) const;
bool Get(size_t index, Value** out_value);
// Convenience forms of Get(). Modifies |out_value| (and returns true)
// only if the index is valid and the Value at that index can be returned
// in the specified form.
// |out_value| is optional and will only be set if non-NULL.
// DEPRECATED, use GetList()::operator[]::GetBool() instead.
bool GetBoolean(size_t index, bool* out_value) const;
// DEPRECATED, use GetList()::operator[]::GetInt() instead.
bool GetInteger(size_t index, int* out_value) const;
// Values of both type Type::INTEGER and Type::DOUBLE can be obtained as
// doubles.
// DEPRECATED, use GetList()::operator[]::GetDouble() instead.
bool GetDouble(size_t index, double* out_value) const;
// DEPRECATED, use GetList()::operator[]::GetString() instead.
bool GetString(size_t index, std::string* out_value) const;
bool GetString(size_t index, string16* out_value) const;
bool GetDictionary(size_t index, const DictionaryValue** out_value) const;
bool GetDictionary(size_t index, DictionaryValue** out_value);
using Value::GetList;
// DEPRECATED, use GetList()::operator[]::GetList() instead.
bool GetList(size_t index, const ListValue** out_value) const;
bool GetList(size_t index, ListValue** out_value);
// Removes the Value with the specified index from this list.
// If |out_value| is non-NULL, the removed Value AND ITS OWNERSHIP will be
// passed out via |out_value|. If |out_value| is NULL, the removed value will
// be deleted. This method returns true if |index| is valid; otherwise
// it will return false and the ListValue object will be unchanged.
// DEPRECATED, use GetList()::erase() instead.
bool Remove(size_t index, std::unique_ptr<Value>* out_value);
// Removes the first instance of |value| found in the list, if any, and
// deletes it. |index| is the location where |value| was found. Returns false
// if not found.
// DEPRECATED, use GetList()::erase() instead.
bool Remove(const Value& value, size_t* index);
// Removes the element at |iter|. If |out_value| is NULL, the value will be
// deleted, otherwise ownership of the value is passed back to the caller.
// Returns an iterator pointing to the location of the element that
// followed the erased element.
// DEPRECATED, use GetList()::erase() instead.
iterator Erase(iterator iter, std::unique_ptr<Value>* out_value);
// Appends a Value to the end of the list.
// DEPRECATED, use GetList()::push_back() instead.
void Append(std::unique_ptr<Value> in_value);
// Convenience forms of Append.
// DEPRECATED, use GetList()::emplace_back() instead.
void AppendBoolean(bool in_value);
void AppendInteger(int in_value);
void AppendDouble(double in_value);
void AppendString(StringPiece in_value);
void AppendString(const string16& in_value);
// DEPRECATED, use GetList()::emplace_back() in a loop instead.
void AppendStrings(const std::vector<std::string>& in_values);
void AppendStrings(const std::vector<string16>& in_values);
// Appends a Value if it's not already present. Returns true if successful,
// or false if the value was already
// DEPRECATED, use std::find() with GetList()::push_back() instead.
bool AppendIfNotPresent(std::unique_ptr<Value> in_value);
// Insert a Value at index.
// Returns true if successful, or false if the index was out of range.
// DEPRECATED, use GetList()::insert() instead.
bool Insert(size_t index, std::unique_ptr<Value> in_value);
// Searches for the first instance of |value| in the list using the Equals
// method of the Value type.
// Returns a const_iterator to the found item or to end() if none exists.
// DEPRECATED, use std::find() instead.
const_iterator Find(const Value& value) const;
// Swaps contents with the |other| list.
// DEPRECATED, use GetList()::swap() instead.
void Swap(ListValue* other);
// Iteration.
// DEPRECATED, use GetList()::begin() instead.
iterator begin() { return list_.begin(); }
// DEPRECATED, use GetList()::end() instead.
iterator end() { return list_.end(); }
// DEPRECATED, use GetList()::begin() instead.
const_iterator begin() const { return list_.begin(); }
// DEPRECATED, use GetList()::end() instead.
const_iterator end() const { return list_.end(); }
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
ListValue* DeepCopy() const;
// DEPRECATED, use Value::Clone() instead.
// TODO(crbug.com/646113): Delete this and migrate callsites.
std::unique_ptr<ListValue> CreateDeepCopy() const;
};
// This interface is implemented by classes that know how to serialize
// Value objects.
class BASE_EXPORT ValueSerializer {
public:
virtual ~ValueSerializer();
virtual bool Serialize(const Value& root) = 0;
};
// This interface is implemented by classes that know how to deserialize Value
// objects.
class BASE_EXPORT ValueDeserializer {
public:
virtual ~ValueDeserializer();
// This method deserializes the subclass-specific format into a Value object.
// If the return value is non-NULL, the caller takes ownership of returned
// Value. If the return value is NULL, and if error_code is non-NULL,
// error_code will be set with the underlying error.
// If |error_message| is non-null, it will be filled in with a formatted
// error message including the location of the error if appropriate.
virtual std::unique_ptr<Value> Deserialize(int* error_code,
std::string* error_str) = 0;
};
// Stream operator so Values can be used in assertion statements. In order that
// gtest uses this operator to print readable output on test failures, we must
// override each specific type. Otherwise, the default template implementation
// is preferred over an upcast.
BASE_EXPORT std::ostream& operator<<(std::ostream& out, const Value& value);
BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
const DictionaryValue& value) {
return out << static_cast<const Value&>(value);
}
BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
const ListValue& value) {
return out << static_cast<const Value&>(value);
}
// Stream operator so that enum class Types can be used in log statements.
BASE_EXPORT std::ostream& operator<<(std::ostream& out,
const Value::Type& type);
} // namespace base
#endif // BASE_VALUES_H_