通过 Groovy 附加现有的 CSV 文件

编程问答 2022-07-25

问题描述

以下 Groovy 代码可以创建一个新的 CSV 文件（在此示例中为 testfile.csv）并在 CSV 中写入 JSON 数据。 我不想创建新的 CSV 文件，而只想在不覆盖文件的情况下向现有的 testfile.csv 文件添加（追加）几行。有人可以帮助更改以下代码中的哪些内容以强制它附加文件而不是编写新文件吗？我听说过 StandardOpenoption.APPEND，但不知道把它放在哪里。谢谢

import groovy.json.JsonSlurper;
import org.apache.commons.csv.CSVFormat;
import org.apache.commons.csv.CSVPrinter;
import com.oracle.e1.common.orchestrationAttributes;
import java.text.SimpleDateFormat;

HashMap < String,Object > main(orchestrationAttributes orchAttr,HashMap inputMap) {
HashMap < String,Object > returnMap = new HashMap < String,Object > ();
returnMap.put("CSVComplete","false");
// Write the view number after jsonIn.fs_DATAbroWSE_
def jsonIn = new JsonSlurper().parseText(inputMap.get("vendor Data"));
def jsonData = jsonIn.fs_DATAbroWSE_GettingJsonDataFromSomewhere.data.gridData.rowset;

if (jsonData.size() == 0) {
  returnMap.put("CSVComplete","empty");
  return returnMap;
}
def fileName = orchAttr.getTempFileName("testfile.csv");
returnMap.put("CSVOutFileName",fileName);
//class writer to write file def
def sw = new StringWriter();
//build the CSV writer with a header
//def csv = new CSVPrinter(sw,CSVFormat.DEFAULT.withHeader("Business Unit","Document Number","LT","SUB","Amount","HardcodedTHREAD","ApprovedBudget","fromview003"));
  def csv = new CSVPrinter(sw,CSVFormat.DEFAULT); //No header
// create output file
fileCsvOut = new File(fileName);
def count=0;
// build the CSV
def an8Map = new ArrayList();
for (int i = 0; i < jsonData.size(); i++) {
  def businessunit = jsonData[i].table1_column1;
   if (an8Map.contains(businessunit)) {
     continue;
   }
   an8Map.add(businessunit);
   count++;
   csv.printRecord(businessunit,jsonData[i].table_column,jsonData[i].table1_column1,jsonData[i]. table1_column2,jsonData[i]. table1_column3,"Fixed text1 "Fixed text2","Fixedtext3");
}
csv.close();

//writing csv to file
fileCsvOut.withWriter('UTF-8') {
  writer ->
   writer.write(sw.toString()) 
}
orchAttr.writeDebug(sw.toString());
returnMap.put("csv",sw.toString());
returnMap.put("CSVComplete","true");
returnMap.put("CSVcount",Integer.toString(count));
return returnMap;
}

解决方法

使用 withWriterAppend 而不是 withWriter

https://docs.groovy-lang.org/latest/html/groovy-jdk/java/io/File.html#withWriterAppend(java.lang.String,%20groovy.lang.Closure)

csvcsvcsvgroovyjde