为什么序列化LocalDateTime失效?

springboot项目.时间API用的jsr310.

但是发现LocalDateTime返回的时间是数组格式.这也太奇葩了.

所以自己写了个序列化的配置.但是死活不生效.有知道为啥的么?

package com.cpis.modules.twotickets.config.webcontext;

import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalTimeSerializer;
import org.springframework.boot.autoconfigure.jackson.Jackson2ObjectMapperBuilderCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
import java.util.TimeZone;

@Configuration
public class WebConfig implements WebMvcConfigurer {
	
	
	@Bean
	@Primary
	public Jackson2ObjectMapperBuilderCustomizer customizer() {
		return builder -> {
			builder.locale(Locale.CHINA);
			builder.timeZone(TimeZone.getTimeZone(ZoneId.systemDefault()));
			builder.simpleDateFormat("yyyy-MM-dd HH:mm:ss");
			
			JavaTimeModule javaTimeModule = new JavaTimeModule();
			javaTimeModule.addSerializer(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
			javaTimeModule.addSerializer(LocalDate.class, new LocalDateSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
			javaTimeModule.addSerializer(LocalTime.class, new LocalTimeSerializer(DateTimeFormatter.ofPattern("HH:mm:ss")));
			javaTimeModule.addDeserializer(LocalDateTime.class, new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
			javaTimeModule.addDeserializer(LocalDate.class, new LocalDateDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
			javaTimeModule.addDeserializer(LocalTime.class, new LocalTimeDeserializer(DateTimeFormatter.ofPattern("HH:mm:ss")));
			
			builder.modules(javaTimeModule);
		};
	}
}

PS:肯定不能单个注解解决.时间太多了.需要的是全局配置.单个注解我试过,可以解决.但不是我要的全局通用.