refactor entity implemtations

Author: vincentlauvlwj

ktorm-core/src/main/kotlin/me/liuwj/ktorm/entity/Entity.kt

@@ -13,7 +13,7 @@ import kotlin.reflect.full.isSubclassOf
  *
  * 在框架中，实体类必须声明为 interface(not data class) 并且继承 [Entity]。
  * 在从查询结果中创建实体对象时，框架会使用 JDK 动态代理生成实体类接口的实现，并创建一个对象，
- * 因此在实体里上进行的任何操作都会代理到框架的 [EntityImpl] 类中，从而使得框架能够检测到实体对象中的任何变化
+ * 因此在实体里上进行的任何操作都会代理到框架的 [EntityImplementation] 类中，从而使得框架能够检测到实体对象中的任何变化
  *
  * Created by vince on Jun 18, 2018.
  */
@@ -22,12 +22,12 @@ interface Entity<E : Entity<E>> : Serializable {
     /**
      * Return this entity's [KClass] instance, which must be an interface.
      */
-    //val entityClass: KClass<E>
+    val entityClass: KClass<E>
 
     /**
      * Return the immutable view of this entity's all properties.
      */
-    //val properties: Map<String, Any?>
+    val properties: Map<String, Any?>
 
     /**
      * 将实体对象中变化的字段保存到数据库，返回受影响的记录数
@@ -61,7 +61,7 @@ interface Entity<E : Entity<E>> : Serializable {
         /**
          * 创建实体类对象，此方法仅限框架内部使用
          */
-        fun create(entityClass: KClass<*>, parent: Entity<*>? = null, fromTable: Table<*>? = parent?.impl?.fromTable): Entity<*> {
+        internal fun create(entityClass: KClass<*>, parent: EntityImplementation? = null, fromTable: Table<*>? = parent?.fromTable): Entity<*> {
             if (!entityClass.isSubclassOf(Entity::class)) {
                 throw IllegalArgumentException("An entity class must be subclass of Entity.")
             }
@@ -70,22 +70,31 @@ interface Entity<E : Entity<E>> : Serializable {
             }
 
             val classLoader = Thread.currentThread().contextClassLoader
-            val impl = EntityImpl(entityClass, fromTable, parent)
-            return Proxy.newProxyInstance(classLoader, arrayOf(entityClass.java), impl) as Entity<*>
+            val handler = EntityImplementation(entityClass, fromTable, parent)
+            return Proxy.newProxyInstance(classLoader, arrayOf(entityClass.java), handler) as Entity<*>
         }
 
         /**
          * 创建实体类对象
          */
-        inline fun <reified E : Entity<E>> create(): E {
-            return create(E::class, null, null) as E
+        fun create(entityClass: KClass<*>): Entity<*> {
+            if (!entityClass.isSubclassOf(Entity::class)) {
+                throw IllegalArgumentException("An entity class must be subclass of Entity.")
+            }
+            if (!entityClass.java.isInterface) {
+                throw IllegalArgumentException("An entity class must be defined as an interface.")
+            }
+
+            val classLoader = Thread.currentThread().contextClassLoader
+            val handler = EntityImplementation(entityClass, null, null)
+            return Proxy.newProxyInstance(classLoader, arrayOf(entityClass.java), handler) as Entity<*>
         }
 
         /**
-         * 创建实体类对象，并执行回调函数进行初始化操作
+         * 创建实体类对象
          */
-        inline fun <reified E : Entity<E>> create(init: E.() -> Unit): E {
-            return create<E>().apply(init)
+        inline fun <reified E : Entity<E>> create(): E {
+            return create(E::class) as E
         }
     }
 

ktorm-core/src/main/kotlin/me/liuwj/ktorm/entity/EntityDml.kt

@@ -24,7 +24,7 @@ fun <E : Entity<E>> Table<E>.add(entity: E): Int {
         )
     )
 
-    val useGeneratedKey = primaryKey?.binding != null && entity.getPrimaryKeyValue(this) == null
+    val useGeneratedKey = primaryKey?.binding != null && entity.implementation.getPrimaryKeyValue(this) == null
 
     expression.prepareStatement(autoGeneratedKeys = useGeneratedKey) { statement, logger ->
         val effects = statement.executeUpdate().also { logger.debug("Effects: {}", it) }
@@ -35,24 +35,25 @@ fun <E : Entity<E>> Table<E>.add(entity: E): Int {
                     val generatedKey = primaryKey?.sqlType?.getResult(rs, 1)
                     if (generatedKey != null) {
                         logger.debug("Generated Key: {}", generatedKey)
-                        entity.setPrimaryKeyValue(this, generatedKey)
+                        entity.implementation.setPrimaryKeyValue(this, generatedKey)
                     }
                 }
             }
         }
 
-        entity.impl.fromTable = this
-        entity.discardChanges()
+        entity.implementation.fromTable = this
+        entity.implementation.doDiscardChanges()
         return effects
     }
 }
 
 private fun Table<*>.findInsertColumns(entity: Entity<*>): Map<Column<*>, Any?> {
+    val implementation = entity.implementation
     val assignments = LinkedHashMap<Column<*>, Any?>()
 
     for (column in columns) {
         if (column is SimpleColumn && column.binding != null) {
-            val value = entity.getColumnValue(column)
+            val value = implementation.getColumnValue(column)
             if (value != null) {
                 assignments[column] = value
             }
@@ -63,9 +64,9 @@ private fun Table<*>.findInsertColumns(entity: Entity<*>): Map<Column<*>, Any?>
 }
 
 @Suppress("UNCHECKED_CAST")
-internal fun EntityImpl.doFlushChanges(): Int {
-    val fromTable = this.fromTable ?: kotlin.error("The entity is not associated with any table yet.")
-    val primaryKey = fromTable.primaryKey ?: kotlin.error("Table ${fromTable.tableName} doesn't have a primary key.")
+internal fun EntityImplementation.doFlushChanges(): Int {
+    val fromTable = this.fromTable?.takeIf { this.parent == null } ?: error("The entity is not associated with any table yet.")
+    val primaryKey = fromTable.primaryKey ?: error("Table ${fromTable.tableName} doesn't have a primary key.")
     val assignments = findChangedColumns(fromTable).takeIf { it.isNotEmpty() } ?: return 0
 
     val expression = AliasRemover.visit(
@@ -88,12 +89,12 @@ internal fun EntityImpl.doFlushChanges(): Int {
 
     expression.prepareStatement { statement, logger ->
         val effects =  statement.executeUpdate().also { logger.debug("Effects: {}", it) }
-        discardChanges()
+        doDiscardChanges()
         return effects
     }
 }
 
-private fun EntityImpl.findChangedColumns(fromTable: Table<*>): Map<Column<*>, Any?> {
+private fun EntityImplementation.findChangedColumns(fromTable: Table<*>): Map<Column<*>, Any?> {
     val assignments = LinkedHashMap<Column<*>, Any?>()
 
     for (column in fromTable.columns) {
@@ -102,30 +103,34 @@ private fun EntityImpl.findChangedColumns(fromTable: Table<*>): Map<Column<*>, A
         when (binding) {
             is ReferenceBinding -> {
                 if (binding.onProperty.name in changedProperties) {
-                    val child = this[binding.onProperty.name] as Entity<*>?
-                    assignments[column] = child?.getPrimaryKeyValue(binding.referenceTable)
+                    val child = this.getProperty(binding.onProperty.name) as Entity<*>?
+                    assignments[column] = child?.implementation?.getPrimaryKeyValue(binding.referenceTable)
                 }
             }
             is NestedBinding -> {
                 var anyChanged = false
                 var curr: Any? = this
 
                 for ((i, prop) in binding.withIndex()) {
-                    check(curr is Entity<*>?)
+                    check(curr is EntityImplementation?)
 
-                    val changed = if (curr == null) false else prop.name in curr.impl.changedProperties
+                    val changed = if (curr == null) false else prop.name in curr.changedProperties
 
                     if (changed && i > 0) {
                         check(curr != null)
 
-                        if (curr.impl.fromTable != null && curr.getRoot() != this) {
+                        if (curr.fromTable != null && curr.getRoot() != this) {
                             val propPath = binding.subList(0, i + 1).joinToString(separator = ".", prefix = "this.") { it.name }
                             throw IllegalStateException("$propPath may be unexpectedly discarded after flushChanges, please save it to database first.")
                         }
                     }
 
                     anyChanged = anyChanged || changed
-                    curr = curr?.get(prop.name)
+
+                    curr = curr?.getProperty(prop.name)
+                    if (curr is Entity<*>) {
+                        curr = curr.implementation
+                    }
                 }
 
                 if (anyChanged) {
@@ -138,17 +143,17 @@ private fun EntityImpl.findChangedColumns(fromTable: Table<*>): Map<Column<*>, A
     return assignments
 }
 
-private tailrec fun Entity<*>.getRoot(): Entity<*> {
-    val parent = this.impl.parent
+private tailrec fun EntityImplementation.getRoot(): EntityImplementation {
+    val parent = this.parent
     if (parent == null) {
         return this
     } else {
         return parent.getRoot()
     }
 }
 
-internal fun EntityImpl.doDiscardChanges() {
-    val fromTable = this.fromTable ?: kotlin.error("The entity is not associated with any table yet.")
+internal fun EntityImplementation.doDiscardChanges() {
+    val fromTable = this.fromTable?.takeIf { this.parent == null } ?: error("The entity is not associated with any table yet.")
 
     for (column in fromTable.columns) {
         val binding = column.binding?.takeIf { column is SimpleColumn } ?: continue
@@ -165,20 +170,23 @@ internal fun EntityImpl.doDiscardChanges() {
                         break
                     }
 
-                    check(curr is Entity<*>)
-                    curr.impl.changedProperties.remove(prop.name)
+                    check(curr is EntityImplementation)
+                    curr.changedProperties.remove(prop.name)
 
-                    curr = curr[prop.name]
+                    curr = curr.getProperty(prop.name)
+                    if (curr is Entity<*>) {
+                        curr = curr.implementation
+                    }
                 }
             }
         }
     }
 }
 
 @Suppress("UNCHECKED_CAST")
-internal fun EntityImpl.doDelete(): Int {
-    val fromTable = this.fromTable ?: kotlin.error("The entity is not associated with any table yet.")
-    val primaryKey = fromTable.primaryKey ?: kotlin.error("Table ${fromTable.tableName} doesn't have a primary key.")
+internal fun EntityImplementation.doDelete(): Int {
+    val fromTable = this.fromTable?.takeIf { this.parent == null } ?: error("The entity is not associated with any table yet.")
+    val primaryKey = fromTable.primaryKey ?: error("Table ${fromTable.tableName} doesn't have a primary key.")
 
     val expression = AliasRemover.visit(
         expr = DeleteExpression(