ElasticSearch入门（六）SpringBoot2

2401_84414832 2024-08-03 13:33:03 阅读 69

private String author;

@Field(name = “word_count”, type = FieldType.Integer)

private Integer wordCount;

/**

Jackson日期时间序列化问题：

Cannot deserialize value of type java.time.LocalDateTime from String “2020-06-04 15:07:54”: Failed to deserialize java.time.LocalDateTime: (java.time.format.DateTimeParseException) Text ‘2020-06-04 15:07:54’ could not be parsed at index 10

解决：@JsonFormat(pattern = “yyyy-MM-dd HH:mm:ss”)

日期在ES存为long类型

解决：需要加format = DateFormat.custom

java.time.DateTimeException: Unable to obtain LocalDate from TemporalAccessor: {DayOfMonth=5, YearOfEra=2020, MonthOfYear=6},ISO of type java.time.format.Parsed

解决：pattern = “uuuu-MM-dd HH:mm:ss” 即将yyyy改为uuuu，或8uuuu: pattern = “8uuuu-MM-dd HH:mm:ss”

参考：https://www.elastic.co/guide/en/elasticsearch/reference/current/migrate-to-java-time.html#java-time-migration-incompatible-date-formats

@JsonFormat(pattern = “yyyy-MM-dd HH:mm:ss”)

@Field(name = “publish_date”, type = FieldType.Date, format = DateFormat.custom, pattern = “uuuu-MM-dd HH:mm:ss”)

private LocalDateTime publishDate;

}

核心方法

package com.heartsuit.repository;

import java.util.List;

import com.heartsuit.domain.Book;

import org.springframework.data.elasticsearch.annotations.Query;

import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;

/**

@Author Heartsuit

@Date 2020-06-12

public interface BookRepository extends ElasticsearchRepository<Book, String> {

List findByAuthor(String author);

List findByAuthorLike(String author);

List findByTitle(String author);

List findByWordCount(Integer wordCount);

List findByAuthorAndTitle(String author, String title);

@Query(“{“bool” : {“must” : {“match” : {“title” : “?0”}}}}”)

List queryByTitle(String keyword);

}

测试接口

package com.heartsuit.controller;

import com.heartsuit.domain.Book;

import com.heartsuit.repository.BookRepository;

import lombok.extern.slf4j.Slf4j;

import org.springframework.format.annotation.DateTimeFormat;

import org.springframework.web.bind.annotation.*;

import java.time.LocalDateTime;

import java.util.*;

/**

@Author Heartsuit

@Date 2020-06-12

@RestController

@RequestMapping(“/books”)

@Slf4j

public class BookController {

private final BookRepository bookRepository;

public BookController(BookRepository bookRepository) {

this.bookRepository = bookRepository;

}

@GetMapping(“/all”)

public List findAll() {

Iterable result = bookRepository.findAll();

Iterator res = result.iterator();

List books = new ArrayList<>();

while (res.hasNext()) {

books.add(res.next());

}

log.info(“List All, Size: {}”, books.size());

return books;

}

/**

新增

@param book

@return

@PostMapping(“/”)

public Book create(@RequestBody Book book) {

log.info(“Saved OK: {}”, book.getTitle());

return bookRepository.save(book);

}

/**

根据ID查询

@param id

@return

@GetMapping(“/{id}”)

public Book findById(@PathVariable(“id”) String id) {

log.info(“Query ID: {}”, id);

Book orElse = bookRepository.findById(id).orElse(null);

return orElse;

}

/**

根据ID修改

@param id

@param title

@param author

@param wordCount

@param publishDate

@return

Note: 报错：Failed to convert value of type ‘java.lang.String’ to required type ‘java.time.LocalDateTime’;

解决：在参数前添加注解：@DateTimeFormat(pattern = “yyyy-MM-dd HH:mm:ss”)

@PutMapping(“/{id}”)

public Book update(@PathVariable(“id”) String id,

@RequestParam(name = “title”, required = false) String title,

@RequestParam(name = “author”, required = false) String author,

@RequestParam(name = “wordCount”, required = false) Integer wordCount,

@RequestParam(name = “publishDate”, required = false) @DateTimeFormat(pattern = “yyyy-MM-dd HH:mm:ss”) LocalDateTime publishDate) {

Optional optional = bookRepository.findById(id);

if (optional.isPresent()) {

Book book = optional.get();

if (title != null) {

book.setTitle(title);

}

if (author != null) {

book.setAuthor(author);

}

if (wordCount != null) {

book.setWordCount(wordCount);

}

if (publishDate != null) {

book.setPublishDate(publishDate);

}

return bookRepository.save(book);

}

return null;

}

/**

根据ID删除

@param id

@DeleteMapping(“/{id}”)

public void delete(@PathVariable(“id”) String id) {

log.info(“Deleted ID: {}”, id);

bookRepository.deleteById(id);

}

/**

删除所有

@PostMapping(“/clear”)

public void clear() {

log.info(“Delete All!”);

bookRepository.deleteAll();

}

/**

根据作者查询

@param author

@return

@PostMapping(“/author”)

public List byAuthor(String author) {

log.info(“By Author”);

return bookRepository.findByAuthor(author);

}

/**

根据作者检索

@param author

@return

@PostMapping(“/author/like”)

public List byAuthorLike(String author) {

log.info(“By Author Like”);

return bookRepository.findByAuthorLike(author);

}

/**

根据标题查询

@param title

@return

@PostMapping(“/title”)

public List byTitle(String title) {

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