java后端开发（五）：前端如何理解后端的对象信息

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dGhpcyBpcyBhIGV4YW1wbGU=

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@RestController
@RequestMapping("/web")
public class TestController {

	@GetMapping("/jsonstr")
	public Home getHome() {
		return new Home("家庭", "湖边");
	}
}

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/**
  * 将对象转换成JSON字符串的处理类
  */
public class JsonMapper {

	public static void main(String[] args) {
		JsonMapper mapper = new JsonMapper();

		Home home = new Home("thing", "hangzhou");
		String jsonStr = mapper.parseJson(home);
		System.out.println(jsonStr);

		People people = new People("男", "周");
		String jsonStr2 = mapper.parseJson(people);
		System.out.println(jsonStr2);
	}

	/**
	 * 将传入的对象中的具有 getter方法的属性及其值转变为 JSON 字符串进行输出
	 * 简单处理，默认所有成员都具有 getter方法。
	 * @param obj 传入的对象
	 * @return JSON字符串
	 */
	public String parseJson(Object obj) {
		StringBuilder builder = new StringBuilder("{");
		BeanProperty[] properties = getBeanProperty(obj);

		// 构造JSON字符串
		for (BeanProperty property : properties) {
			builder.append(""").append(property.getName()).append("":"");
			try {
				builder.append(property.getGetter().invoke(obj).toString()).append("",");
			} catch (IllegalAccessException | InvocationTargetException e) {
				e.printStackTrace();
			}
		}
		builder = builder.replace(builder.length() - 1, builder.length(), "}");

		return builder.toString();
	}

	/**
	 * 将对象转换成 BeanProperty 数组
	 * 每个 BeanProperty 都包含了对象中的一个属性的名字和其对应的getter方法
	 * @param obj 对象
	 * @return BeanProperty[] 数组
	 */
	private BeanProperty[] getBeanProperty(Object obj) {
		Class c = obj.getClass();
		// 获取对象中的成员属性
		Field[] fields = c.getDeclaredFields();

		BeanProperty[] beanProperties = new BeanProperty[fields.length];
		// 获取对象本身包含的方法
		Method[] methods = c.getDeclaredMethods();
		// 遍历成员，根据成员信息获取对应的getter方法；
		for (int i = 0; i < fields.length; i++) {
			Field field = fields[i];
			for (Method method : methods) {
				if (method.getName().toLowerCase().equals("get" + field.getName().toLowerCase())) {
					BeanProperty beanProperty = new BeanProperty(field.getName(), method);
					beanProperties[i] = beanProperty;
					break;
				}
			}
		}

		return beanProperties;
	}

	/**
	 * 对象中的属性类
	 * 包含每个属性的名称，每个属性对应的 getter 方法
	 */
	private class BeanProperty {
		private String name;

		private Method getter;

		BeanProperty(String name, Method getter) {
			this.name = name;
			this.getter = getter;
		}

		String getName() {
			return name;
		}

		void setName(String name) {
			this.name = name;
		}

		Method getGetter() {
			return getter;
		}

		void setGetter(Method getter) {
			this.getter = getter;
		}
	}
}

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public class Home {

	private String name;

	private String address;

	public Home() {
	}

	public Home(String name, String address) {
		this.name = name;
		this.address = address;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getAddress() {
		return address;
	}

	public void setAddress(String address) {
		this.address = address;
	}
}

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public class Home {

	private String name;

	private String address;

	private String lon;

	public String ele = "0.01";

	private static String staticStr = "static";

	public Home() {
	}

	public Home(String name, String address) {
		this.name = name;
		this.address = address;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getAddress() {
		return address;
	}

	public void setAddress(String address) {
		this.address = address;
	}

	public String getLat() {
		return "lat";
	}

	public String getStaticStr() {
		return staticStr;
	}

	public static String getStaticString() {
		return "static1";
	}

	public static String getStatics() {
		return "ssss";
	}
}

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@RestController
@RequestMapping("/web")
public class TestController {

	@GetMapping("/jsonstr")
	public Home getHome() {
		return new Home("家庭", "湖边");
	}

	@PostMapping("/param")
	public void url(String u, @RequestHeader String h, @RequestBody Home home) {
		System.out.println(u);
		System.out.println(h);
		System.out.println(home.getName() + "..." + home.getAddress());
	}
}

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this is url
this is header
this is home name...this is home address