Tips ： When the article is finished , Directories can be generated automatically , How to generate it, please refer to the help document on the right

One 、 Preface

Recently received a demand , Generate test data for multiple tables to test the front-end statistics page Some fields require selection from fixed values department , Personnel and other requirements are in Chinese Dates are required in certain time periods … wait

Of course, the first thing I thought of was writing tools , Then generate the corresponding data . But next time, if there is such a demand , Do I have to write one by one , Can you simplify .
This method can solve the problem of quickly generating test data from a single table , The data generated by multi table association still needs to be studied

Last , I thought of writing a test data batch generation tool for entity classes , The demonstration is as follows

Two 、 effect

First create the entity class

Entity class

public class TestEntity {
    
    private String name;
    private Integer age;
    private String tel;
    private String dept;
    private Date date;  
}

Generate data SQL And implement

3、 ... and 、 Realization principle

Generate test data according to entity classes , The core principles of implementation are annotation and reflection , It mainly goes through the following three steps

Get the annotation attributes and parameters of the entity

Currently, the only supported data types are String,int Date type
First, get the attributes of the incoming class and the parameters annotated on the attributes
Field[] fields = aClass.getDeclaredFields();
StringConfigure stringConfigure = field.getAnnotation(StringConfigure.class);
among ,String Types of data support the most generation methods , Take an example to illustrate , Here are String Detailed parameters of annotation of type

@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
public @interface StringConfigure {
    
    // The column name of this attribute in the database 
    String fieldName() default "";
    // Rules for generating test data ,NAME,TELNUMBER,UUID16,UUID,METHOD
    StringRule createRule() default StringRule.UUID16;
    // When createRule  by METHOD The following two parameters take effect 
    // Used to indicate custom parameter generation rules 
    Class aClass() default Class.class;
    String method() default "";
}

Execute the method to obtain test data according to the attributes of the entity

Reflection method internal call RandUtils Method , Such as ：
String s = RandUtils.uuId();
RandUtils.uuId16();
RandUtils.name();
Of course, you can use custom tools to generate data

When the built-in string generation method cannot meet the requirements , You need to specify a custom method to generate strings , have access to StringConfigure Comments are indicated by the following parameters
The following example indicates the use of DefaultList Class getDept Method to generate a string
Be careful :
Method must have no parameters , The return value is String type

@StringConfigure(createRule = StringRule.METHOD,aClass = DefaultList.class, method = "getDept")
    private String dept;
// Here are 
public class DefaultList {
    
    private static String[] deptList=new String[]{
    " Product management module "," Tmall information service is limited "," Technology management section "," R & D department "," Manufacturing department "," Product development department "," Material department "
            ," Equipment department "," Customer service department "," Import and export department "," Information Department "," Planning Department "," Public relations "," The personnel department "," Financial business module "};
    public DefaultList() {
    
    }
    public static String getDept() {
    
        return deptList[RandUtils.num(0,deptList.length-1)];
    }
}

The assembly test data is SQL

StringBuffer sql = new StringBuffer("INSERT INTO " + tableName + " (");
for (int i = 0; i < fields.length; i++) {
    
            Field field=fields[i];
             sql=sql.append(fieldName+") values (");
 }

Core source code

public static String createSql(Class aClass, String tableName) throws Exception {
    
        Field[] fields = aClass.getDeclaredFields();
        Class<DefaultList> randListClass = DefaultList.class;
        Method[] randListClassDeclaredMethods = randListClass.getDeclaredMethods();
        StringBuffer sql = new StringBuffer("INSERT INTO " + tableName + " (");
        for (int i = 0; i < fields.length; i++) {
    
            Field field=fields[i];
            StringConfigure stringConfigure = field.getAnnotation(StringConfigure.class);
            DateConfigure dateConfigure = field.getAnnotation(DateConfigure.class);
            IntConfigure intConfigure = field.getAnnotation(IntConfigure.class);
            String fieldName=null;
            if (intConfigure != null) {
    
                fieldName=intConfigure.fieldName();
            } else if (dateConfigure != null) {
    
                fieldName=dateConfigure.fieldName();
            } else if (stringConfigure != null) {
    
                fieldName=stringConfigure.fieldName();
            }
            if (fieldName.equals("")){
    
                fieldName=field.getName();
            }
            if (i!= fields.length-1){
    
                sql=sql.append(fieldName+",");
            }else {
    
                sql=sql.append(fieldName+") values (");
            }

        }
        for (int i = 0; i < fields.length; i++) {
    
            Field field=fields[i];
            String appendS=null;
            StringConfigure stringConfigure = field.getAnnotation(StringConfigure.class);
            DateConfigure dateConfigure = field.getAnnotation(DateConfigure.class);
            IntConfigure intConfigure = field.getAnnotation(IntConfigure.class);
            if (intConfigure!=null){
    
                int min = intConfigure.min();
                int max = intConfigure.max();
                int num = RandUtils.num(min, max);
                appendS=String.valueOf(num);
            }else if(dateConfigure!=null){
    
                String end = dateConfigure.end();
                String start = dateConfigure.start();
                Date date = RandUtils.date(start, end,"yyyy-MM-dd HH:mm:ss");
                appendS="'"+date2String(date)+"'";
            }
            else if(stringConfigure!=null){
    
                StringRule rule = stringConfigure.createRule();
                if (rule.equals(StringRule.UUID)){
    
                    String s = RandUtils.uuId();
                    appendS="'"+s+"'";
                }
                else if (rule.equals(StringRule.UUID16)){
    
                    appendS="'"+RandUtils.uuId16()+"'";
                }
                else if (rule.equals(StringRule.NAME)){
    
                    appendS="'"+RandUtils.name()+"'";
                }
                else if (rule.equals(StringRule.TELNUMBER)){
    
                    appendS="'"+RandUtils.telNum()+"'";
                }
                else if (rule.equals(StringRule.METHOD)){
    
                    Class arrayClass = stringConfigure.aClass();
                    if (!arrayClass.equals(Class.class)){
    
                        aClass=arrayClass;
                    }
                    else {
    
                        aClass= DefaultList.class;
                    }
                    String arrayName = stringConfigure.method();
                    for (Method method : randListClassDeclaredMethods) {
    
                        String name = method.getName();
                        if (arrayName.equals(name)){
    
                            Object o = aClass.newInstance();
                            String strings = (String) method.invoke(o);
                            appendS="'"+strings+"'";
                            break;
                        }
                    }
                }
            }
            if (i!= fields.length-1){
    
                sql=sql.append(appendS+",");
            }else {
    
                sql=sql.append(appendS+");");
            }
        }
        return sql.toString();
    }

Four 、 How to use

1、 Author entity

package com.mabo.example.entity;
import com.mabo.sql.DefaultList;
import com.mabo.sql.StringRule;
import com.mabo.sql.annotation.DateConfigure;
import com.mabo.sql.annotation.IntConfigure;
import com.mabo.sql.annotation.StringConfigure;
import java.util.Date;
public class TestEntity {
    
    @StringConfigure(createRule = StringRule.NAME)
    private String name;
    @IntConfigure(max = 50,min=20)
    private Integer age;
    @StringConfigure(fieldName = "telePhone",createRule = StringRule.TELNUMBER)
    private String tel;
    @StringConfigure(createRule = StringRule.METHOD,aClass = DefaultList.class, method = "getDept")
    private String dept;
    @DateConfigure(start = "2021-07-19 00:00:00",end =  "2022-07-19 00:00:00")
    private Date date;
}

2、 Introduce dependency

Private clothes , The server downloads very fast , There is a demonstration inside demo
Private service download address ： http://47.103.194.1:8081/download/demo?fileName=AutoData.zip
github Download address : https://github.com/MaBo2420935619/AutoData

3、 Execute reflection method generation SQL

package com.mabo.example;
import com.mabo.example.entity.TestEntity;
import com.mabo.sql.CreateSqlReflect;
public class Test {
    
    public static void main(String[] args) throws Exception {
    
        String test = CreateSqlReflect.createSql(TestEntity.class, "TEST", 10);
        System.out.println(test);
    }
}