java导出文件之Excel（CSV）下并以流形式输出

1
2
3
4
5
6
7
8
9
10
<dependency>

    <groupId>net.sourceforge.javacsv</groupId>

    <artifactId>javacsv</artifactId>

    <version>2.0</version>

</dependency>

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
@Test
public void write(){
try {
// 创建CSV写对象
List<Student> ls=new ArrayList<Student>();
for (int i = 0; i <1000000; i++) {
Student s=new Student();
s.setName("小帅"+i);
s.setAge(i);
s.setScore("100"+i);
s.setSex("男"+i);
ls.add(s);
}
//写入临时文件
File tempFile = File.createTempFile("vehicle", ".csv");
CsvWriter csvWriter = new CsvWriter(tempFile.getCanonicalPath(),',', Charset.forName("UTF-8"));
// 写表头
long s= System.currentTimeMillis();
System.err.println();
String[] headers = {"姓名","年龄","编号","性别"};
csvWriter.writeRecord(headers);
for (Student stu : ls) {
csvWriter.write(stu.getName());
csvWriter.write(stu.getAge()+"");
csvWriter.write(stu.getScore());
csvWriter.write(stu.getSex());
csvWriter.endRecord();
}
csvWriter.close();
long e=System.currentTimeMillis();
System.err.println(e-s);;
/**
* 写入csv结束，写出流
*/
java.io.OutputStream out = getResponse.getOutputStream();
byte[] b = new byte[10240];
java.io.File fileLoad = new java.io.File(tempFile.getCanonicalPath());
getResponse.reset();
getResponse.setContentType("application/csv");
getResponse.setHeader("content-disposition", "attachment; filename=vehicleModel.csv");
long fileLength = fileLoad.length();
String length1 = String.valueOf(fileLength);
getResponse.setHeader("Content_Length", length1);
java.io.FileInputStream in = new java.io.FileInputStream(fileLoad);
int n;
while ((n = in.read(b)) != -1) {
out.write(b, 0, n); //每次写入out1024字节
}
in.close();
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}