2021-01-27 GraphQL入门（一）
GraphQL GraphQL既是一种用于API的查询语言也是一个满足你数据查问的运行时。GraphQL对你的API中的数据提供了一套易于了解的残缺形容，使得客户端可能精确地取得它须要的数据，而且没有任何冗余，也让API更容易地随着时间推移而演进，还能用于构建弱小的开发工具。

启动后界面如上图所示

1.1 增加依赖 org.springframework.boot spring-boot-starter

    <dependency>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-web</artifactId>    </dependency>    <dependency>        <groupId>com.graphql-java</groupId>        <artifactId>graphql-java-tools</artifactId>        <version>5.2.4</version>    </dependency>    <dependency>        <groupId>com.graphql-java</groupId>        <artifactId>graphql-spring-boot-starter</artifactId>        <version>5.0.2</version>    </dependency>    <dependency>        <groupId>com.graphql-java</groupId>        <artifactId>graphiql-spring-boot-starter</artifactId>        <version>5.0.2</version>    </dependency>    <dependency>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-test</artifactId>        <scope>test</scope>    </dependency>

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1.2 编写graphqls文件 type Query { pets: [Pet] animals: [Animal] }

type Pet { id: Int type: Animal name: String age: Int }

enum Animal { DOG CAT BADGER MAMMOTH OOOOOO } 自己用的idea编写graphqls文件，能够装置graphql插件，

配置文件类型

1.3 编写实体类 package com.example.demo;

public class Pet { private long id;

private String name;

private Animal type;

private int age;

public Pet(long id, String name, Animal type, int age) {

this.id = id;this.name = name;this.type = type;this.age = age;

}

public Pet() {

}

public long getId() {

return id;

}

public void setId(long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public Animal getType() {

return type;

}

public void setType(Animal type) {

this.type = type;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}
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} package com.example.demo;

public enum Animal { /* Animal */ DOG, CAT, BADGER, MAMMOTH, OOOOOO } 1.4 编写查问组件 package com.example.demo;

import com.coxautodev.graphql.tools.GraphQLQueryResolver; import org.springframework.stereotype.Component;

import java.util.ArrayList; import java.util.List;

@Component public class Query implements GraphQLQueryResolver { public List pets() { List pets = new ArrayList<>();

Pet aPet = new Pet();aPet.setId(1L);aPet.setName("Covey's cat");aPet.setAge(3);aPet.setType(Animal.CAT);pets.add(aPet);return pets;

}

public List<Animal> animals() {

Animal animal = Animal.MAMMOTH;Animal animal1 = Animal.BADGER;Animal animal2 = Animal.CAT;Animal animal3 = Animal.OOOOOO;Animal animal4 = Animal.DOG;List<Animal> animalList = new ArrayList<>(4);animalList.add(animal);animalList.add(animal1);animalList.add(animal2);animalList.add(animal3);animalList.add(animal4);return animalList;

}
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} 本章节介绍完，前面待续...

参考资料：

github.com/graphql-jav…

www.graphql-java.com/tutorials/g…

graphql.cn/code/#serve…