Question

我在我的项目中使用Spring 5。直到今天，还有方法CrudRepository#findOne。

但是在下载最新快照后它突然消失了！有没有提到该方法现在不可用？

我的依赖列表：

apply plugin: 'java'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'


repositories {
    mavenCentral()
    maven { url "https://repo.spring.io/snapshot" }
    maven { url "https://repo.spring.io/milestone" }
}    

dependencies {
    compile 'org.springframework.boot:spring-boot-starter-validation'
    compile 'org.springframework.boot:spring-boot-starter-web'
    compile 'org.springframework.boot:spring-boot-starter-data-jpa'
    runtime 'org.springframework.boot:spring-boot-devtools'

    runtime 'com.h2database:h2:1.4.194'
    compile 'org.projectlombok:lombok:1.16.14'
    compile 'org.modelmapper:modelmapper:0.7.5'


    testCompile 'org.springframework.boot:spring-boot-starter-test'

    testCompile 'org.codehaus.groovy:groovy-all:2.4.10'

    testCompile 'cglib:cglib:3.2.5'
    testCompile 'org.spockframework:spock-core:1.0-groovy-2.4'
}

更新

似乎此方法已替换为CrudRepository#findById

Answer 1

请参阅与DATACMNS-944相关联的this commit，该https://developer.android.com/studio/publish/app-signing.html#google-play-app-signing具有以下重命名

╔═════════════════════╦═══════════════════════╗
║      Old name       ║       New name        ║
╠═════════════════════╬═══════════════════════╣
║ findOne(…)          ║ findById(…)           ║
╠═════════════════════╬═══════════════════════╣
║ save(Iterable)      ║ saveAll(Iterable)     ║
╠═════════════════════╬═══════════════════════╣
║ findAll(Iterable)   ║ findAllById(…)        ║
╠═════════════════════╬═══════════════════════╣
║ delete(ID)          ║ deleteById(ID)        ║
╠═════════════════════╬═══════════════════════╣
║ delete(Iterable)    ║ deleteAll(Iterable)   ║
╠═════════════════════╬═══════════════════════╣
║ exists()            ║ existsById(…)         ║
╚═════════════════════╩═══════════════════════╝

Answer 2

请注意，findById并非findOne的确切替代，而是返回Optional而不是null。

我不太熟悉新的java事情，我花了一点时间才弄明白，但这会将findById行为变成findOne行为：

return rep.findById(id).orElse(null);

Answer 3

我们有数百种旧的import os import math import random import time #set up screen screen = turtle.Screen() screen.bgcolor("green") screen.title("Pong") # set up border border_pen = turtle.Turtle() border_pen.speed(0) border_pen.color("white") border_pen.penup() border_pen.setposition(-300,-300) border_pen.pendown() border_pen.pensize(3) for side in range(4): border_pen.fd(600) border_pen.lt(90) border_pen.hideturtle() #set score to 0 score = 0 #set time to zero time = 0 seconds = 0 #Draw score score_pen = turtle.Turtle() score_pen.speed(0) score_pen.color("white") score_pen.penup() score_pen.setposition(-290, 310) scorestring = "Score %s" %score score_pen.write(scorestring, False, align="left", font= ("Arial", 14, "normal")) score_pen.hideturtle() #Draw timer time_pen = turtle.Turtle() time_pen.speed(0) time_pen.color("white") time_pen.penup() time_pen.setposition(260, 310) timestring = "Time %s" %time time_pen.write(timestring, False, align="left", font= ("Arial", 14, "normal")) time_pen.hideturtle() #create the player turtle player = turtle.Turtle() player.color("blue") player.shape("square") player.shapesize(0.5, 4) player.penup() player.speed(0) player.setposition(-280,-250)#(x,y) player.setheading(90) playerspeed = 15 #create the AIplayer turtle AIplayer = turtle.Turtle() AIplayer.color("black") AIplayer.shape("square") AIplayer.shapesize(0.5, 4) AIplayer.penup() AIplayer.speed(0) AIplayer.setposition(280,250)#(x,y) AIplayer.setheading(90) AIplayerspeed = 15 #create the pong pong = turtle.Turtle() pong.color("red") pong.shape("circle") pong.shapesize(0.5, 0.5) pong.penup() pong.speed(10) pong.setposition(0,0)#(x,y) pongspeed = 15 pong.goto(0, 265) pong.dy = -5 pong.dx = 5 #Move player up and down def move_up(): y = player.ycor() y += playerspeed if y > 265: y = 260 player.sety(y) def move_down(): y = player.ycor() y -= playerspeed if y < -265: y = -260 player.sety(y) #keyboard bindings turtle.listen() turtle.onkey(move_up, "Up") turtle.onkey(move_down, "Down") #turtle.onkey(fire_bullet, "space") def isCollision(t1, t2): distance = math.sqrt(math.pow(t1.xcor()- t2.xcor(),2)+math.pow(t1.ycor()-t2.ycor(),2)) if distance < 20: return True else: return False #main game loop while True: #move pong ball pong.sety(pong.ycor() +pong.dy) pong.setx(pong.xcor() +pong.dx) #check for bounce and redirect it if pong.ycor() < -300: pong.dy *= -1 if pong.ycor() > 300: pong.dy *= -1 if pong.xcor() < -300: pong.dx *= -1 print("Game Over") exit() if pong.xcor() > 300: pong.dx *= -1 #move AI paddle (might speed up pong movement) y = pong.ycor() y += AIplayerspeed AIplayer.sety(y) if AIplayer.ycor() > 265: AIplayerspeed *= -1 if AIplayer.ycor() < -250: AIplayerspeed *= -1 #collision pong and player if isCollision(pong, player): pong.dy *= -1 pong.dx *= -1 #Update the score score += 10 scorestring = "Score: %s" %score score_pen.clear() score_pen.write(scorestring, False, align="left", font=("Arial", 14, "normal")) #collision pong and AIplayer if isCollision(pong, AIplayer): pong.dy *= -1 pong.dx *= -1 #updates timer and increases ball speed if seconds > 29: pong.dy *= -2 pong.dx *= -2 if seconds > 59: pong.dy *= -3 pong.dx *= -3 #displays timer but makes game laggy # seconds += 0.1 # time = seconds # timestring = "Time: %s" %time # time_pen.clear() # time_pen.write(timestring, False, align="Left", font=("Arial", 14, "normal"))方法的用法。我们没有进行庞大的重构，而是创建了以下中间接口，并让我们的存储库扩展了它，而不是直接扩展findOne()

JpaRepository

Answer 4

实用转型

旧方式：

Entity aThing = repository.findOne(1L);

新方式：

Optional<Entity> aThing = repository.findById(1L);

Answer 5

另一种方式。添加一个@Query。即使我更喜欢使用Optional：

@Repository
public interface AccountRepository extends JpaRepository<AccountEntity, Long> {

    @Query("select a from AccountEntity a where a.id=?1")
    public AccountEntity findOne(Long id);

缺少CrudRepository＃findOne方法

5 个答案: