Java 实现 对象和转字符串之间的互转 （json格式）

<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.9.7</version> </dependency> <dependency> <groupId>com.squareup.retrofit2</groupId> <artifactId>converter-gson</artifactId> <version>2.5.0</version> </dependency>