Java实现PDF在线预览
@RequestMapping("/preview1")
public void er(HttpServletResponse response){
File file = new File("G:\\桌面\\Thymeleaf3.0中文翻译文档@www.java1234.com.pdf");
if (file.exists()){
byte[] data = null;
try {
FileInputStream input = new FileInputStream(file);
data = new byte[input.available()];
input.read(data);
response.getOutputStream().write(data);
input.close();
} catch (Exception e) {
System.out.println(e);
}
}else{
return;
}
}
@ResponseBody
@RequestMapping("/preview2")
public void findPdf( HttpServletResponse response) throws IOException{
response.setContentType("application/pdf");
FileInputStream in = new FileInputStream(new File("G:\\桌面\\Thymeleaf3.0中文翻译文档@www.java1234.com.pdf"));
OutputStream out = response.getOutputStream();
byte[] b = new byte[512];
while ((in.read(b))!=-1) {
out.write(b);
}
out.flush();
in.close();
out.close();
}
@ResponseBody
@RequestMapping("/preview3")
public void devDoc(HttpServletRequest request, HttpServletResponse response, String storeName) throws Exception {
request.setCharacterEncoding("UTF-8");
String ctxPath = request.getSession().getServletContext().getRealPath("");
String downLoadPath = "G:\\桌面\\Thymeleaf3.0中文翻译文档@www.java1234.com.pdf";
response.setContentType("application/pdf");
FileInputStream in = new FileInputStream(new File(downLoadPath));
OutputStream out = response.getOutputStream();
byte[] b = new byte[1024];
while ((in.read(b))!=-1) {
out.write(b);
}
out.flush();
in.close();
out.close();
}
@ResponseBody
@RequestMapping("/preview")
public void download( HttpServletResponse response
) throws IOException {
String filePath = "G:\\桌面\\Thymeleaf3.0中文翻译文档@www.java1234.com.pdf";
System.out.println("filePath:" + filePath);
File f = new File(filePath);
if (!f.exists()) {
response.sendError(404, "File not found!");
return;
}
BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));
byte[] bs = new byte[1024];
int len = 0;
response.reset(); // 非常重要
if (true) { // 在线打开方式
URL u = new URL("file:///" + filePath);
String contentType = u.openConnection().getContentType();
response.setContentType(contentType);
response.setHeader("Content-Disposition", "inline;filename="
+ "2019年上半年英语四级笔试准考证(戴林峰).pdf");
// 文件名应该编码成utf-8，注意：使用时，我们可忽略这句
} else {
// 纯下载方式
response.setContentType("application/x-msdownload");
response.setHeader("Content-Disposition", "attachment;filename="
+ "2019年上半年英语四级笔试准考证(戴林峰).pdf");
}
OutputStream out = response.getOutputStream();
while ((len = br.read(bs)) > 0) {
out.write(bs, 0, len);
}
out.flush();
out.close();
br.close();
}
Java快捷实现PDF在线预览
本文章利用各个浏览器的内核支持PDF预览功能来做，PDF的预览网上说的最多的是PDF.JS实现预览，也找了好多文章，死活最后实现不了，通过这个方法解决了，如果有PDF.js解决的可以大家沟通交流下。
这里提一下，其他word和excel可以通过aspose代码转换成PDF，也很快有效。可以网上搜下。
方法很简单，首先引入的都是IO的包。
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import org.apache.commons.io.IOUtils;接下来就是在自己的后台controller里面写个方法。里面file的文件可以通过参数或是封装方式获取，这个里面的流不需要关闭，浏览器会自动获取然后展示。关闭的话浏览器就无法加载！
@RequestMapping(value = "/showpdf")
public void showpdf(HttpServletRequest request, HttpServletResponse response, Model model) {
try {
File file = new File("D:/xyptFile/java.pdf");
FileInputStream fileInputStream = new FileInputStream(file);
response.setHeader("Content-Type", "application/pdf");
OutputStream outputStream = response.getOutputStream();
IOUtils.write(IOUtils.toByteArray(fileInputStream), outputStream);
} catch(Exception e) {
e.printStackTrace();
}
}文章来源：从其他各个文章中测试验证，取得最优方案。
以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程网。
