EntityMapper

EntityMapper is a Java library that simplifies object mapping. Inspired by Bean.copyProperties, it offers enhanced functionality for transferring data between objects, going beyond basic property copying to provide a more powerful and flexible solution for complex mapping scenarios.

Features

• Simple and Easy to Use: Provides a concise API for convenient object mapping.
• Flexible Configuration: Supports various mapping methods, including direct assignment, type conversion, and custom mapping.

GUIDE Quick Start

1. Add Dependency

<dependency>
  <groupId>com.ksptool</groupId>
  <artifactId>entity-mapper</artifactId>
  <version>2.0A</version> 
</dependency>

2. Entities Class: Simplified Object Mapping

The Entities class in EntityMapper provides a static, convenient way to perform object mapping without directly instantiating the Any class. This guide focuses on the as and assign methods for quick and easy object transformations.

as Method

The as method creates a new instance of the target type and maps the source object's properties to it.

TestStaff source = new TestStaff();
source.setName("test");
TestStaffVo target = Entities.as(source, TestStaffVo.class); 
assertEquals("test", target.getName()); 

List<TestStaff> staffList = ....
List<TestStaffVo> target = Entities.as(staffList, TestStaffVo.class);

assign Method

The assign method is an alias for the second form of the as method. It maps properties from the source object to an existing target object.

TestStaff source = new TestStaff();
source.setName("test");
TestStaffVo target = new TestStaffVo();

Entities.assign(source, target); // Same as Entities.as(source, target)
assertEquals("test", target.getName());

Any Class: Flexible Object Mapping

The Any class is the core of EntityMapper, providing a fluent and versatile API for object mapping. This guide explores its key features and demonstrates how to leverage its flexibility for various mapping scenarios.

Creating an Any Instance

You can create an Any instance in two ways:

1. From scratch: Use Any.of() to create an empty Any instance and build it step by step.
2. From an existing object: Use Any.of(object) to create an Any instance that wraps an existing object.

Core Mapping Methods

• val(String propertyName, Object value): Sets the value of a property in the target object.

  • Use this to add properties, modify existing ones, or even set values for nested properties.

• as(Class<T> targetClass): Transforms the current Any instance into an object of the specified targetClass.

• asList(Class<T> targetClass): Transforms a collection wrapped in the current Any instance into a list of objects of the specified targetClass.

Advanced Mapping Features

• matchUpdate(String propertyName): Starts a conditional mapping block where you can define rules to update a property based on its current value.

• eq(Object oldValue, Object newValue): Within a matchUpdate block, this defines a rule to replace oldValue with newValue for the specified property.

• fin(): Ends a matchUpdate block.

• to(Class<T> targetClass): Initiates an asymmetric mapping process, allowing you to map properties with different names or perform custom logic before finalizing the mapping with get().

• get(): Finalizes an asymmetric mapping process and returns the mapped object.

EntityMapper

EntityMapper 是一个简化对象映射的 Java 库。它受到 Bean.copyProperties 的启发，提供了增强的功能来传输对象之间的数据，超越了基本属性复制，为复杂映射场景提供更强大、更灵活的解决方案。

功能特性

• 简单易用： 提供简洁的 API，方便进行对象映射。
• 灵活配置： 支持多种映射方法，包括直接赋值、类型转换和自定义映射。

快速入门指南

1. 添加依赖

<dependency>
  <groupId>com.ksptool</groupId>
  <artifactId>entity-mapper</artifactId>
  <version>2.0A</version> 
</dependency>

2. Entities 类：简化的对象映射

EntityMapper 中的 Entities 类提供了一种静态的、便捷的方式来执行对象映射，而无需直接实例化 Any 类。本指南重点介绍 as 和 assign 方法，用于快速简便的对象转换。

as 方法

as 方法用于创建目标类型的新实例，并将一个源对象的所有属性映射至新实例。

TestStaff source = new TestStaff();
source.setName("test");
TestStaffVo target = Entities.as(source, TestStaffVo.class); 
assertEquals("test", target.getName()); 

映射List

List<TestStaff> staffList = ....
List<TestStaffVo> target = Entities.as(staffList, TestStaffVo.class);

assign 方法

assign 方法是 as 方法的一种别名。它可以将源对象的属性映射到一个现有的目标对象。

TestStaff source = new TestStaff();
source.setName("test");
TestStaffVo target = new TestStaffVo();

Entities.assign(source, target); // Same as Entities.as(source, target)
assertEquals("test", target.getName());

Any 类：灵活的对象映射

Any 类是 EntityMapper 的核心，它提供了一个流畅且通用的对象映射 API。本指南探讨了它的主要功能，并演示了如何利用它的灵活性来处理各种映射场景。

创建 Any 实例

妳可以通过两种方式创建Any实例:

1. 从头开始: 使用 Any.of() 创建一个空的 Any 实例, 并逐步构建它.

TestStaff staff = Any.of()
        .val("id", 123456L)
        .val("name", "Steve")
        .as(TestStaff.class);

2. 从现有对象: 使用 Any.of(object) 创建一个包装现有对象的 Any 实例

TestStaff staff = new TestStaff();
staff.setStaffId(123456L);
staff.setName("Steve");

TestStaffVo staffVo = Any.of(staff)
        .to(TestStaffVo.class)
        .val("id", staff.getStaffId())
        .get();

System.out.println(staffVo.getId());

核心映射方法

• val(String propertyName, Object value): 设置目标对象中属性的值。

  • 使用此方法添加属性、修改现有属性，甚至可以设置嵌套属性的值。

• as(Class<T> targetClass): 将当前的Any 实例转换为指定 targetClass的对象.

• asList(Class<T> targetClass): 将当前 Any 实例中包装的集合转换为指定 targetClass的对象列表

高级映射功能

• matchUpdate(String propertyName): 启动一个条件映射块，您可以在其中定义基于当前值更新属性的规则。

• eq(Object oldValue, Object newValue): 在 matchUpdate 块内, 这定义了一个将指定属性的 oldValue 替换为 newValue 的规则.

• fin(): 结束 matchUpdate 块.

• to(Class<T> targetClass): 启动非对称映射过程，允许您映射具有不同名称的属性，或使用 get() 完成映射之前执行自定义逻辑。

• get(): 完成非对称映射过程并返回映射后的对象。

高级映射功能

List<TestStaff> list = new ArrayList<>();

for(int i = 0; i < 32; i++){
    list.add(Any.of()
            .val("name", "Steve"+i)
            .val("gender",18)
            .as(TestStaff.class)
    );
}
//以上代码用于创建一个包含Staff对象的集合

//使用Any将集合中name字段为Steve3的对象修改为JackHorse
List<TestStaffVo> vos = Any.of(list)
        .matchUpdate("name")
        .eq("Steve3", "JackHorse")
        .asList(TestStaffVo.class);

assertEquals("JackHorse", vos.get(3).getName());