题
任何人都可以推荐一个简单的API,将允许我使用读CSV输入文件,做一些简单的变革,然后把它写。
一个快速的谷歌已经找到了 http://flatpack.sourceforge.net/ 这看起来很有希望。
我只是想来看看有什么其他人正在使用之前,我的夫妇自己这个API。
解决方案
Apache Commons CSV
检查了 Apache共同CSV.
这个图书馆的读和写 若干变化的CSV, ,其中包括该标准的一个 RFC4180.也读写 卡分隔 文件。
- Excel
- InformixUnload
- InformixUnloadCsv
- MySQL
- Oracle
- PostgreSQLCsv
- PostgreSQLText
- RFC4180
- TDF
其他提示
更新: 代码在这个答案是超级CSV1.52.更新的代码实例超CSV2.4.0可能被发现在该项目的网站:http://super-csv.github.io/super-csv/index.html
该SuperCSV项目的直接支持的分析和结构化的操纵CSV细胞。从 http://super-csv.github.io/super-csv/examples_reading.html 你会发现例如
给出一个类
public class UserBean {
String username, password, street, town;
int zip;
public String getPassword() { return password; }
public String getStreet() { return street; }
public String getTown() { return town; }
public String getUsername() { return username; }
public int getZip() { return zip; }
public void setPassword(String password) { this.password = password; }
public void setStreet(String street) { this.street = street; }
public void setTown(String town) { this.town = town; }
public void setUsername(String username) { this.username = username; }
public void setZip(int zip) { this.zip = zip; }
}
和你有一个CSV文件的标题。让我们假设以下内容
username, password, date, zip, town
Klaus, qwexyKiks, 17/1/2007, 1111, New York
Oufu, bobilop, 10/10/2007, 4555, New York
然后,您可以创建一个实例UserBean和填充值自第二线的文件,与下列代码
class ReadingObjects {
public static void main(String[] args) throws Exception{
ICsvBeanReader inFile = new CsvBeanReader(new FileReader("foo.csv"), CsvPreference.EXCEL_PREFERENCE);
try {
final String[] header = inFile.getCSVHeader(true);
UserBean user;
while( (user = inFile.read(UserBean.class, header, processors)) != null) {
System.out.println(user.getZip());
}
} finally {
inFile.close();
}
}
}
使用下面的"操作规范"
final CellProcessor[] processors = new CellProcessor[] {
new Unique(new StrMinMax(5, 20)),
new StrMinMax(8, 35),
new ParseDate("dd/MM/yyyy"),
new Optional(new ParseInt()),
null
};
阅读CSV格式的描述让我感觉到使用第3党库将低头痛于编写它自己:
维基百科列出了10个或一些已知的图书馆:
我比较库列出使用某些种类的检查清单。 OpenCSV 变成了一个赢家我(情况因人而异),结果如下:
+ maven
+ maven - release version // had some cryptic issues at _Hudson_ with snapshot references => prefer to be on a safe side
+ code examples
+ open source // as in "can hack myself if needed"
+ understandable javadoc // as opposed to eg javadocs of _genjava gj-csv_
+ compact API // YAGNI (note *flatpack* seems to have much richer API than OpenCSV)
- reference to specification used // I really like it when people can explain what they're doing
- reference to _RFC 4180_ support // would qualify as simplest form of specification to me
- releases changelog // absence is quite a pity, given how simple it'd be to get with maven-changes-plugin // _flatpack_, for comparison, has quite helpful changelog
+ bug tracking
+ active // as in "can submit a bug and expect a fixed release soon"
+ positive feedback // Recommended By 51 users at sourceforge (as of now)
我们使用 JavaCSV, ,它工作得很好
最后一企业应用程序,我的工作,需要处理的一个显着数量的CSV--几个月前-我用的 SuperCSV 在sourceforge和找到简单、稳健和问题。
你可以使用csvreader api和下载了从以下地点:
http://sourceforge.net/projects/javacsv/files/JavaCsv/JavaCsv%202.1/javacsv2.1.zip/download
或
http://sourceforge.net/projects/javacsv/
使用下列代码:
/ ************ For Reading ***************/
import java.io.FileNotFoundException;
import java.io.IOException;
import com.csvreader.CsvReader;
public class CsvReaderExample {
public static void main(String[] args) {
try {
CsvReader products = new CsvReader("products.csv");
products.readHeaders();
while (products.readRecord())
{
String productID = products.get("ProductID");
String productName = products.get("ProductName");
String supplierID = products.get("SupplierID");
String categoryID = products.get("CategoryID");
String quantityPerUnit = products.get("QuantityPerUnit");
String unitPrice = products.get("UnitPrice");
String unitsInStock = products.get("UnitsInStock");
String unitsOnOrder = products.get("UnitsOnOrder");
String reorderLevel = products.get("ReorderLevel");
String discontinued = products.get("Discontinued");
// perform program logic here
System.out.println(productID + ":" + productName);
}
products.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
写/追加CSV文件
代码:
/************* For Writing ***************************/
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import com.csvreader.CsvWriter;
public class CsvWriterAppendExample {
public static void main(String[] args) {
String outputFile = "users.csv";
// before we open the file check to see if it already exists
boolean alreadyExists = new File(outputFile).exists();
try {
// use FileWriter constructor that specifies open for appending
CsvWriter csvOutput = new CsvWriter(new FileWriter(outputFile, true), ',');
// if the file didn't already exist then we need to write out the header line
if (!alreadyExists)
{
csvOutput.write("id");
csvOutput.write("name");
csvOutput.endRecord();
}
// else assume that the file already has the correct header line
// write out a few records
csvOutput.write("1");
csvOutput.write("Bruce");
csvOutput.endRecord();
csvOutput.write("2");
csvOutput.write("John");
csvOutput.endRecord();
csvOutput.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
还有 CSV/Excel用.它假定所有这些数据表格和提供的数据迭代器。
CSV格式听起来很容易用于StringTokenizer但它可以成为更加复杂。在这里,在德国号是用作一个分隔和细胞中含有符需要逃脱。你不会到处理,很容易与StringTokenizer.
如果你打算读csv从excel,然后还有一些有趣的角情况。我不可能记住他们所有,但apache commons csv是不能够处理它正确地(例如,url).
一定要试验的excel出的报价和逗号和斜线所有的地方。