swift-java-coder/Sources/JavaEncoder.swift

531 lines
20 KiB
Swift

//
// JavaEncoder.swift
// jniBridge
//
// Created by Andrew on 10/14/17.
//
import Foundation
import CoreFoundation
import java_swift
public enum MissingFieldsStrategy: Error {
case `throw`
case ignore
}
public enum JavaCodingError: Error {
case notSupported(String)
case cantCreateObject(String)
case cantFindObject(String)
case nilNotSupported(String)
case wrongArrayLength
}
indirect enum JNIStorageType {
case primitive(name: String)
case object(className: String)
case array(type: JNIStorageType)
case dictionary
var sig: String {
switch self {
case .primitive(let name):
return name
case .array(let type):
return "[\(type.sig)"
case .object(let className):
return "L\(className);"
case .dictionary:
return "L\(JavaHashMapClassname);"
}
}
}
class JNIStorageObject {
let type: JNIStorageType
let javaObject: jobject
init(type: JNIStorageType, javaObject: jobject) {
self.type = type
self.javaObject = javaObject
}
deinit {
JNI.api.DeleteLocalRef(JNI.env, javaObject)
}
}
/// `JavaEncoder` facilitates the encoding of `Encodable` values into JSON.
open class JavaEncoder: Encoder {
// MARK: Properties
/// The path to the current point in encoding.
public var codingPath: [CodingKey]
/// Contextual user-provided information for use during encoding.
public var userInfo: [CodingUserInfoKey : Any] {
return [:]
}
fileprivate let package: String
fileprivate var javaObjects: [JNIStorageObject]
fileprivate let missingFieldsStrategy: MissingFieldsStrategy
// MARK: - Constructing a JSON Encoder
/// Initializes `self` with default strategies.
public init(forPackage: String, missingFieldsStrategy: MissingFieldsStrategy = .throw) {
self.codingPath = [CodingKey]()
self.package = forPackage
self.javaObjects = [JNIStorageObject]()
self.missingFieldsStrategy = missingFieldsStrategy
}
// MARK: - Encoding Values
/// Encodes the given top-level value and returns its JSON representation.
///
/// - parameter value: The value to encode.
/// - returns: A new `Data` value containing the encoded JSON data.
/// - throws: `EncodingError.invalidValue` if a non-conforming floating-point value is encountered during encoding, and the encoding strategy is `.throw`.
/// - throws: An error if any value throws an error during encoding.
open func encode<T : Encodable>(_ value: T) throws -> jobject {
do {
let storage = try self.box(value)
assert(self.javaObjects.count == 0, "Missing encoding for \(self.javaObjects.count) objects")
return JNI.api.NewLocalRef(JNI.env, storage.javaObject)!
}
catch {
// clean all reference if failed
self.javaObjects.removeAll()
throw error
}
}
// MARK: - Encoder Methods
public func container<Key>(keyedBy: Key.Type) -> KeyedEncodingContainer<Key> {
let storage = self.popInstance()
switch storage.type {
case .dictionary:
let container = JavaHashMapContainer<Key>(referencing: self, codingPath: self.codingPath, jniStorage: storage)
return KeyedEncodingContainer(container)
case let .object(className):
let container = JavaObjectContainer<Key>(referencing: self, codingPath: self.codingPath, javaClass: className, jniStorage: storage)
return KeyedEncodingContainer(container)
default:
fatalError("Only keyed containers")
}
}
public func unkeyedContainer() -> UnkeyedEncodingContainer {
let storage = self.popInstance()
return JavaArrayContainer(referencing: self, codingPath: self.codingPath, jniStorage: storage)
}
public func singleValueContainer() -> SingleValueEncodingContainer {
let storage = self.popInstance()
switch storage.type {
case let .object(className):
return JavaEnumValueEncodingContainer(encoder: self, javaClass: className, jniStorage: storage)
default:
fatalError("Only object type supported here")
}
}
}
// MARK: - Encoding Containers
fileprivate class JavaObjectContainer<K : CodingKey> : KeyedEncodingContainerProtocol {
typealias Key = K
// MARK: Properties
/// A reference to the encoder we're writing to.
private let encoder: JavaEncoder
private let javaClass: String
private let jniStorage: JNIStorageObject
/// The path of coding keys taken to get to this point in encoding.
private(set) public var codingPath: [CodingKey]
// MARK: - Initialization
/// Initializes `self` with the given references.
fileprivate init(referencing encoder: JavaEncoder, codingPath: [CodingKey], javaClass: String, jniStorage: JNIStorageObject) {
self.encoder = encoder
self.codingPath = codingPath
self.javaClass = javaClass
self.jniStorage = jniStorage
}
private var javaObject: jobject {
return jniStorage.javaObject
}
// MARK: - KeyedEncodingContainerProtocol Methods
public func encodeNil(forKey key: Key) throws {
throw JavaCodingError.notSupported("JavaObjectContainer.encodeNil(forKey: \(key)")
}
public func encode(_ value: Bool, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "Z")
JNI.api.SetBooleanField(JNI.env, javaObject, filed, jboolean(value ? JNI_TRUE : JNI_FALSE))
}
public func encode(_ value: Int, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, filed, Int64(value))
}
public func encode(_ value: Int8, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "B")
JNI.api.SetByteField(JNI.env, javaObject, filed, value)
}
public func encode(_ value: Int16, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "S")
JNI.api.SetShortField(JNI.env, javaObject, filed, value)
}
public func encode(_ value: Int32, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "I")
JNI.api.SetIntField(JNI.env, javaObject, filed, jint(value))
}
public func encode(_ value: Int64, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, filed, value)
}
public func encode(_ value: UInt, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, filed, jlong(bitPattern: UInt64(value)))
}
public func encode(_ value: String, forKey key: Key) throws {
let filed = try getJavaField(forClass: javaClass, field: key.stringValue, sig: "Ljava/lang/String;")
var locals = [jobject]()
JNI.check(JNI.api.SetObjectField(JNI.env, javaObject, filed, value.localJavaObject(&locals)), &locals)
}
public func encode<T : Encodable>(_ value: T, forKey key: Key) throws {
do {
let object = try self.encoder.box(value)
let filed = try getJavaField(forClass: self.javaClass, field: key.stringValue, sig: object.type.sig)
JNI.api.SetObjectField(JNI.env, self.javaObject, filed, object.javaObject)
}
catch {
if self.encoder.missingFieldsStrategy == .ignore {
// Ignore
}
else {
throw error
}
}
}
public func nestedContainer<NestedKey>(keyedBy keyType: NestedKey.Type, forKey key: Key) -> KeyedEncodingContainer<NestedKey> {
preconditionFailure("Not implemented: nestedContainer")
}
public func nestedUnkeyedContainer(forKey key: Key) -> UnkeyedEncodingContainer {
preconditionFailure("Not implemented: nestedUnkeyedContainer")
}
public func superEncoder() -> Encoder {
preconditionFailure("Not implemented: superEncoder")
}
public func superEncoder(forKey key: Key) -> Encoder {
preconditionFailure("Not implemented: superEncoder")
}
}
// MARK: - Encoding Containers
fileprivate class JavaHashMapContainer<K : CodingKey> : KeyedEncodingContainerProtocol {
typealias Key = K
// MARK: Properties
/// A reference to the encoder we're writing to.
private let encoder: JavaEncoder
private let jniStorage: JNIStorageObject
private var javaPutMethod = try! getJavaMethod(forClass: JavaHashMapClassname, method: "put", sig: "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;")
/// The path of coding keys taken to get to this point in encoding.
private(set) public var codingPath: [CodingKey]
// MARK: - Initialization
/// Initializes `self` with the given references.
fileprivate init(referencing encoder: JavaEncoder, codingPath: [CodingKey], jniStorage: JNIStorageObject) {
self.encoder = encoder
self.codingPath = codingPath
self.jniStorage = jniStorage
}
private var javaObject: jobject {
return jniStorage.javaObject
}
// MARK: - KeyedEncodingContainerProtocol Methods
public func encodeNil(forKey key: Key) throws {
throw JavaCodingError.notSupported("JavaHashMapContainer.encodeNil(forKey: \(key))")
}
public func encode(_ value: String, forKey key: Key) throws {
var locals = [jobject]()
var args = [jvalue]()
args.append(jvalue(l: key.stringValue.localJavaObject(&locals)))
args.append(jvalue(l: value.localJavaObject(&locals)))
withUnsafePointer(to: &args[0]) { argsPtr in
let result = JNI.check(JNI.api.CallObjectMethodA(JNI.env, javaObject, javaPutMethod, argsPtr), &locals)
assert(result == nil, "Rewrite for key \(key.stringValue)")
}
}
public func encode<T : Encodable>(_ value: T, forKey key: Key) throws {
if value is String {
try self.encode(value as! String, forKey: key)
return
}
let object = try self.encoder.box(value)
var locals = [jobject]()
var args = [jvalue]()
args.append(jvalue(l: key.stringValue.localJavaObject(&locals)))
args.append(jvalue(l: object.javaObject))
withUnsafePointer(to: &args[0]) { argsPtr in
let result = JNI.check(JNI.api.CallObjectMethodA(JNI.env, javaObject, javaPutMethod, argsPtr), &locals)
assert(result == nil, "Rewrite for key \(key.stringValue)")
}
}
public func nestedContainer<NestedKey>(keyedBy keyType: NestedKey.Type, forKey key: Key) -> KeyedEncodingContainer<NestedKey> {
preconditionFailure("Not implemented: nestedContainer")
}
public func nestedUnkeyedContainer(forKey key: Key) -> UnkeyedEncodingContainer {
preconditionFailure("Not implemented: nestedUnkeyedContainer")
}
public func superEncoder() -> Encoder {
preconditionFailure("Not implemented: superEncoder")
}
public func superEncoder(forKey key: Key) -> Encoder {
preconditionFailure("Not implemented: superEncoder")
}
}
fileprivate class JavaArrayContainer : UnkeyedEncodingContainer {
// MARK: Properties
/// A reference to the encoder we're writing to.
private let encoder: JavaEncoder
/// The path of coding keys taken to get to this point in encoding.
private(set) public var codingPath: [CodingKey]
/// The number of elements encoded into the container.
public private(set) var count: Int = 0
private let jniStorage: JNIStorageObject
// MARK: - Initialization
/// Initializes `self` with the given references.
fileprivate init(referencing encoder: JavaEncoder, codingPath: [CodingKey], jniStorage: JNIStorageObject) {
self.encoder = encoder
self.codingPath = codingPath
self.jniStorage = jniStorage
}
private var javaObject: jobject {
return jniStorage.javaObject
}
// MARK: - UnkeyedEncodingContainer Methods
public func encodeNil() throws {
throw JavaCodingError.notSupported("JavaArrayContainer.encodeNil")
}
public func encode(_ value: Int) throws {
var value = jlong(value)
JNI.api.SetLongArrayRegion(JNI.env, self.javaObject, jsize(count), 1, &value)
count += 1
}
public func encode(_ value: String) throws {
var locals = [jobject]()
JNI.check(JNI.api.SetObjectArrayElement(JNI.env,
self.javaObject,
jsize(self.count),
value.localJavaObject(&locals)), &locals)
count += 1
}
public func encode<T : Encodable>(_ value: T) throws {
if value is String {
try self.encode(value as! String)
return
}
if value is Int {
try self.encode(value as! Int)
return
}
let storeObject = try self.encoder.box(value)
JNI.api.SetObjectArrayElement(JNI.env,
self.javaObject,
jsize(self.count),
storeObject.javaObject)
count += 1
}
public func nestedContainer<NestedKey>(keyedBy keyType: NestedKey.Type) -> KeyedEncodingContainer<NestedKey> {
preconditionFailure("Not implemented: nestedContainer")
}
public func nestedUnkeyedContainer() -> UnkeyedEncodingContainer {
preconditionFailure("Not implemented: nestedUnkeyedContainer")
}
public func superEncoder() -> Encoder {
preconditionFailure("Not implemented: superEncoder")
}
}
class JavaEnumValueEncodingContainer: SingleValueEncodingContainer {
var codingPath: [CodingKey]
let encoder: JavaEncoder
private var javaClass: String
private var jniStorage: JNIStorageObject
init(encoder: JavaEncoder, javaClass: String, jniStorage: JNIStorageObject) {
self.codingPath = [CodingKey]()
self.encoder = encoder
self.javaClass = javaClass
self.jniStorage = jniStorage
}
private var javaObject: jobject {
return jniStorage.javaObject
}
public func encodeNil() throws {
throw JavaCodingError.notSupported("JavaSingleValueEncodingContainer.encodeNil")
}
public func encode<T : Encodable>(_ value: T) throws {
if value is Int {
let fieldID = try getJavaField(forClass: javaClass, field: "rawValue", sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, fieldID, jlong(value as! Int))
return
}
if value is UInt {
let filed = try getJavaField(forClass: javaClass, field: "rawValue", sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, filed, jlong(bitPattern: UInt64(value as! UInt)))
return
}
if value is UInt32 {
let filed = try getJavaField(forClass: javaClass, field: "rawValue", sig: "J")
JNI.api.SetLongField(JNI.env, javaObject, filed, jlong(value as! UInt32))
return
}
throw JavaCodingError.notSupported("JavaSingleValueEncodingContainer.encode(value: \(value) \(type(of:value))")
}
}
private var UriClass = JNI.GlobalFindClass("android/net/Uri")
private var UriConstructor = JNI.api.GetStaticMethodID(JNI.env, JNI.GlobalFindClass("android/net/Uri"), "parse", "(Ljava/lang/String;)Landroid/net/Uri;")
extension JavaEncoder {
fileprivate func getFullClassName<T>(_ value: T) -> String{
if value is [String: Encodable] {
return JavaHashMapClassname
}
return package + "/" + String(describing: type(of: value))
}
@discardableResult
fileprivate func box<T: Encodable>(_ value: T) throws -> JNIStorageObject {
let storage: JNIStorageObject
if T.self == URL.self {
var locals = [jobject]()
let javaString = (value as! URL).absoluteString.localJavaObject(&locals)
var args = [jvalue]()
args.append(jvalue(l: javaString))
let uriObject = JNIMethod.CallStaticObjectMethod(className: "android/net/Uri",
classCache: &UriClass,
methodName: "parse",
methodSig: "(Ljava/lang/String;)Landroid/net/Uri;",
methodCache: &UriConstructor,
args: &args,
locals: &locals)
storage = JNIStorageObject.init(type: .object(className: "android/net/Uri"), javaObject: uriObject!)
}
else if T.self == [String].self {
let value = value as! [String]
let javaClass = try getJavaClass(JavaStringClassname)
guard let javaObject = JNI.api.NewObjectArray(JNI.env, jsize(value.count), javaClass, nil) else {
throw JavaCodingError.cantCreateObject("\(JavaStringClassname)[]")
}
storage = JNIStorageObject(type: .array(type: .object(className: JavaStringClassname)), javaObject: javaObject)
javaObjects.append(storage)
try value.encode(to: self)
}
else if T.self == [Int].self {
let value = value as! [Int]
guard let javaObject = JNI.api.NewLongArray(JNI.env, jsize(value.count)) else {
throw JavaCodingError.cantCreateObject("long[]")
}
storage = JNIStorageObject(type: .array(type: .primitive(name: "J")), javaObject: javaObject)
javaObjects.append(storage)
try value.encode(to: self)
}
else if let valueEncodableArray = value as? [Encodable] {
let subType = String("\(T.self)".dropFirst(6)).dropLast(1)
let fullClassName = package + "/" + subType
let javaClass = try getJavaClass(fullClassName)
guard let javaObject = JNI.api.NewObjectArray(JNI.env, jsize(valueEncodableArray.count), javaClass, nil) else {
throw JavaCodingError.cantCreateObject("\(fullClassName)[]")
}
storage = JNIStorageObject(type: .array(type: .object(className: fullClassName)), javaObject: javaObject)
javaObjects.append(storage)
try value.encode(to: self)
}
else {
let storageType: JNIStorageType
let fullClassName: String
if value is [String: Encodable] {
fullClassName = JavaHashMapClassname
storageType = .dictionary
}
else {
fullClassName = package + "/" + String(describing: type(of: value))
storageType = .object(className: fullClassName)
}
let javaClass = try getJavaClass(fullClassName)
let emptyContructor = try getJavaEmptyConstructor(forClass: fullClassName)
guard let javaObject = JNI.api.NewObjectA(JNI.env, javaClass, emptyContructor, nil) else {
throw JavaCodingError.cantCreateObject(fullClassName)
}
storage = JNIStorageObject(type: storageType, javaObject: javaObject)
javaObjects.append(storage)
try value.encode(to: self)
}
return storage
}
fileprivate func popInstance() -> JNIStorageObject {
guard let javaObject = self.javaObjects.popLast() else {
preconditionFailure("No instances in stack")
}
return javaObject
}
}