Error: "package com.fasterxml.jackson.databind does not exist" when compiling Java file

Question

我在 Eclipse 上创建了一个 Maven 项目，并在 pom.xml 文件中添加了以下依赖项：

<dependency>
        <groupId>com.fasterxml</groupId>
        <artifactId>jackson-xml-databind</artifactId>
        <version>0.6.2</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.13.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.13.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.13.0</version>
</dependency>

然后我用下面的代码检查依赖是否可以编译：

import com.fasterxml.jackson.databind.ObjectMapper;

public class App 
{
    
    public static void main(String[] args) {
        ObjectMapper mapper = new ObjectMapper();
        
    }

}

虽然 Eclipse 没有显示任何错误，但当我使用以下命令编译它时：

$ javac -sourcepath src  src\main\java\App.java

我收到以下 3 个错误：

src\main\java\App.java:6: error: package com.fasterxml.jackson.databind does not exist
import com.fasterxml.jackson.databind.ObjectMapper;
                                     ^
src\main\java\App.java:16: error: cannot find symbol
                ObjectMapper mapper = new ObjectMapper();
                ^
  symbol:   class ObjectMapper
  location: class App
src\main\java\App.java:16: error: cannot find symbol
                ObjectMapper mapper = new ObjectMapper();
                                          ^
  symbol:   class ObjectMapper
  location: class App
3 errors

请记住，依赖项对应的JAR文件已安装到计算机上的maven存储库中

Answer 1

看起来你的项目是基于 maven 的，使用 maven 命令编译它： cd 到包含 pom.xml 和运行的目录： mvn 编译

Error: "package com.fasterxml.jackson.databind does not exist" when compiling Java file

Error: "package com.fasterxml.jackson.databind does not exist" when compiling Java file

java

eclipse

maven

jackson

jackson-databind