博客
关于我
如何在Java中生成大量随机CSV文件
阅读量:732 次
发布时间:2019-03-22

本文共 2853 字,大约阅读时间需要 9 分钟。

The CSV format remains one of the simplest and most widely used methods for data exchange. Its popularity has led to a constant need for developers to generate large volumes of CSV files for testing purposes. My latest open source project aims to address this need.

This project, , is a Java library designed to help developers generate randomized data files. Currently, it supports CSV and Fixed Width formats, with plans to expand to JSON formats in the future.

This guide will walk you through generating a simple CSV file using the library and the Faker library for random data generation.

Maven Integration

For Maven projects, you can add the required dependencies to your project's pom.xml file by including the following XML snippet:

au.com.anthonybruno        SdGen        0.3.0                com.github.javafaker        javafaker        0.14

Instructions

First, obtain an instance of the Faker class with the following code:

Faker faker = Faker.instance();

Next, use the Faker instance to generate values like URLs or names using methods such as faker.internet().url() or faker.space().planet().

To create the structure for your CSV file, use the SDGen builder. Start with:

Gen.start()

Then, add fields using the addField method. This method takes two parameters: the field name (used to identify the column in the generated file) and a generator (a simple interface with a single method to generate random values). Here's how to add "First Name" and "Last Name" fields:

Gen.start()    .addField("First Name", () -> faker.name().firstName())    .addField("Last Name", () -> faker.name().lastName())

For the "Age" field, you can use SDGen's built-in generator with specified min and max values:

Gen.start()    .addField("First Name", () -> faker.name().firstName())    .addField("Last Name", () -> faker.name().lastName())    .addField("Age", new IntGenerator(18, 80))

Next, specify the number of rows to generate and select the output format. For CSV files, you can use:

Gen.start()    .addField("First Name", () -> faker.name().firstName())    .addField("Last Name", () -> faker.name().lastName())    .addField("Age", new IntGenerator(18, 80))    .generate(1000)    .asCsv()

Finally, specify how to output the data. Use the toFile method to save the generated data to a file:

Gen.start()    .addField("First Name", () -> faker.name().firstName())    .addField("Last Name", () -> faker.name().lastName())    .addField("Age", new IntGenerator(18, 80))    .generate(1000)    .asCsv()    .toFile("people.csv");

That's it! Running the code will generate a CSV file in your project's working directory. Here's an example of the generated data:

First Name,Last Name,Age  
Corrine,Berge,78
Gerald,Carter,63
Enid,Padberg,66
Eleanora,Murray,79
Coy,Okuneva,76
Jovan,Reynolds,77
Lane,Haag,48

For more details about SDGen, visit its official website.

转载地址:http://qmwwk.baihongyu.com/

你可能感兴趣的文章
mysql 让所有IP访问数据库
查看>>
mysql 记录的增删改查
查看>>
MySQL 设置数据库的隔离级别
查看>>
MySQL 证明为什么用limit时,offset很大会影响性能
查看>>
Mysql 语句操作索引SQL语句
查看>>
MySQL 误操作后数据恢复(update,delete忘加where条件)
查看>>
MySQL 调优/优化的 101 个建议!
查看>>
mysql 转义字符用法_MySql 转义字符的使用说明
查看>>
mysql 输入密码秒退
查看>>
mysql 递归查找父节点_MySQL递归查询树状表的子节点、父节点具体实现
查看>>
mysql 通过查看mysql 配置参数、状态来优化你的mysql
查看>>
mysql 里对root及普通用户赋权及更改密码的一些命令
查看>>
Mysql 重置自增列的开始序号
查看>>
mysql 锁机制 mvcc_Mysql性能优化-事务、锁和MVCC
查看>>
MySQL 错误
查看>>
mysql 随机数 rand使用
查看>>
MySQL 面试题汇总
查看>>
MySQL 面试,必须掌握的 8 大核心点
查看>>
MySQL 高可用性之keepalived+mysql双主
查看>>
MySQL 高性能优化规范建议
查看>>