java中使用PrintWriter将国际字符写入HttpServletResponse时，显示为ä½ å¥½

Question

When we write a chinese content which is got as response from a REST call to HttpServletResponse using PrintWriter as below, then, the issue occurs. In the servlet when we use the below code, it gets downloaded as CSV. The downloaded CSV has ä½ å¥½. Sample code which is used.

// Sample Chinese content got as response from REST call
String content ="你好";
response.setContentType("text/csv; charset=UTF-8");
response.addHeader("Content-Disposition", "attachment; filename=Name.csv");

PrintWriter out = response.getWriter();
out.print(content);
out.flush();
out.close();

Could someone help in providing a way to print these characters as such in the csv file.

Answer 1

The cause of this problem is the specification of Excel and Java. Excel expects the CSV files are encoded in UTF-8 with BOM, while Java writes UTF-8 without BOM.

As @VGR said in the comment, you have to add BOM ( \ ) at the top of the CSV file like this:

response.setContentType("text/csv; charset=UTF-8");
response.addHeader("Content-Disposition", "attachment; filename=Name.csv");
response.getWriter().print("\ufeff");
response.getWriter().print("你好\n");
response.getWriter().print("再见\n");