【发布时间】：2018-08-28 10:17:41
【问题描述】：
在我最近的spring项目中，我需要从html页面生成一个pdf文件。我正在尝试使用WkhtmlToPdf 完成这项任务。但我无法从 html 页面生成 pdf 文件。我搜索了很多关于WkhtmlToPdf 的项目和教程，但我没有找到任何答案。我在这里发布我的代码。
这是我的控制器类，它重定向到带有学生列表的 html 页面
@Controller
public class TestController {
@Autowired
StudentService studentService;
@Autowired
PdfDemo pdfDemo;
@GetMapping("/test")
private String testPage(Model model)
{
List<Student> studentList = studentService.findAll();
System.out.println(studentList);
model.addAttribute(studentList);
return "sample";
}
}
这是我的显示学生列表的 html 页面
<body>
<div class="container" id="pdfDiv">
<h2>HTML Table</h2>
<table class="table table-striped">
<tr>
<th>Id</th>
<th>Name</th>
<th>Session</th>
<th>Department</th>
<th>Roll</th>
<th>Mobile</th>
</tr>
<tr th:each="student : ${studentList}">
<td th:text="${student.id}"></td>
<td th:text="${student.name}"></td>
<td th:text="${student.session}"></td>
<td th:text="${student.department}"></td>
<td th:text="${student.roll}"></td>
<td th:text="${student.mobile}"></td>
</tr>
</table>
</div>
<a href="#" th:href="@{/getStudentsListAsPdf}">Download PDF</a>
</body>
在这里你可以看到，我有一个生成pdf的链接。 PdfGenerateController 类是
@Controller
public class PdfGenerateController {
@GetMapping("/getStudentsListAsPdf")
public ResponseEntity<Resource> generateReportOfStudent() {
String downloadFilePath = generatePdfListForStudents();
System.out.println("DL File Path: "+downloadFilePath);
if (downloadFilePath == null)
throw new NullPointerException("data missing");
if (downloadFilePath == null)
return ResponseEntity.badRequest()
.contentType(MediaType.parseMediaType("application/pdf"))
.body(null);
File file = new File(downloadFilePath);
Path path = Paths.get(file.getAbsolutePath());
ByteArrayResource resource = null;
try {
resource = new ByteArrayResource(Files.readAllBytes(path));
} catch (IOException e) {
e.printStackTrace();
}
HttpHeaders headers = new HttpHeaders();
headers.add("Content-Disposition", "attachment; filename=\"student_list" + ".pdf\"");
return ResponseEntity.ok()
.headers(headers)
.contentLength(file.length())
.contentType(MediaType.parseMediaType("application/pdf"))
.body(resource);
}
}
这是编写代码以生成pdf的类
@Service
public class PdfDemo {
@Value("${file.download.base}")
private String DOWNLOAD_FOLDER;
public static final String DOWNLOAD_PATH = "tmp/downloads/";
public static final String ZIP_PATH = "/tmp/zip_files";
public static final String FILE_NAME = "student_list";
public static final String SERVER_REPORT_URL = "/report/html";
public static final String DOWNLOAD_FILE_PATH = DOWNLOAD_PATH + FILE_NAME;
public static final String ZIPFILE = "/tmp/zip_files/cmed_report.zip";
public static final String ZIPFILE_NAME = "cmed_report.zip";
public static final String SRCDIR = "/tmp/downloads";
public static final String DATE_FORMAT_PATTERN = "yyyy-MM-dd-HH";
public static String getBaseURL() throws MalformedURLException {
HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder
.getRequestAttributes()).getRequest();
String baseUrl = "";
if (request != null) {
// handle proxy forward
String scheme = request.getScheme();
if (request.getHeader("x-forwarded-proto") != null) {
scheme = request.getHeader("x-forwarded-proto");
}
Integer serverPort = request.getServerPort();
if ((serverPort == 80) || (serverPort == 443)) {
// No need to add the server port for standard HTTP and HTTPS ports, the scheme will help determine it.
baseUrl = String.format("%s://%s%s", scheme, request.getServerName(), request.getContextPath());
} else {
baseUrl = String.format("%s://%s:%d%s", scheme, request.getServerName(), serverPort, request.getContextPath());
}
}
return baseUrl;
}
public static String generatePdfListForStudents()
{
WkHtmlToPdf pdf = new WkHtmlToPdf();
try {
pdf.addSources(Source.fromUrl(getServerAbsolutePath(SERVER_REPORT_URL)));
System.out.println("Server absolute path: " + getServerAbsolutePath(SERVER_REPORT_URL));
System.out.println(Source.fromUrl(getServerAbsolutePath(SERVER_REPORT_URL)));
} catch (Exception e) {
e.printStackTrace();
}
String downloadPath = DOWNLOAD_FILE_PATH + ".pdf";
pdf.addArguments(
Argument.from(EnableJavascript));
System.out.println("PDF Location: " + downloadPath);
// Save the PDF
File file = new File(downloadPath);
System.out.println("Directory status: " + file.exists() + " " + file.isDirectory());
try {
System.out.println("Paths.get: " + Paths.get(downloadPath));
pdf.save(Paths.get(downloadPath));
} catch (IOException e) {
e.printStackTrace();
}
return downloadPath;
}
public static String getServerAbsolutePath(String requestPath) throws MalformedURLException {
String URL = getBaseURL() + requestPath;
return URL;
}
}
这是SERVER_REPORT_URL 在PdfDemo 类中的Controller 类
@Controller
public class HtmlViewReportController {
@Autowired
StudentService studentService;
@GetMapping(value = "/report/html")
public String getPdfReportForStudent(Model model) {
model.addAttribute("studentList", studentService.findAll());
return "sample";
}
}
现在，当我在 html 页面中点击 Download PDF时，我得到了 error。此处的错误堆栈跟踪
java.io.IOException: Cannot run program "wkhtmltopdf": error=2, No such file or directory
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
at java.lang.Runtime.exec(Runtime.java:620)
at java.lang.Runtime.exec(Runtime.java:528)
at com.ztomic.wkhtmltopdf.WkHtmlToPdf.convert(WkHtmlToPdf.java:84)
at com.ztomic.wkhtmltopdf.WkHtmlToPdf.getPdfBytes(WkHtmlToPdf.java:77)
at com.ztomic.wkhtmltopdf.WkHtmlToPdf.save(WkHtmlToPdf.java:68)
at com.avijit.test.PdfUtil.PdfDemo.generatePdfListForStudents(PdfDemo.java:109)
at com.avijit.test.Controller.PdfGenerateController.generateReportOfStudent(PdfGenerateController.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:155)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:123)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:108)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:800)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:800)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1471)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.io.IOException: error=2, No such file or directory
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
at java.lang.ProcessImpl.start(ProcessImpl.java:134)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
... 71 more
DL File Path: tmp/downloads/student_list.pdf
java.nio.file.NoSuchFileException: /home/dracula/IdeaProjects/WkhtmlToPdfGeneratorProject/tmp/downloads/student_list.pdf
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:86)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)
at sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:214)
at java.nio.file.Files.newByteChannel(Files.java:361)
at java.nio.file.Files.newByteChannel(Files.java:407)
at java.nio.file.Files.readAllBytes(Files.java:3152)
at com.avijit.test.Controller.PdfGenerateController.generateReportOfStudent(PdfGenerateController.java:43)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:155)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:123)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:108)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:800)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:800)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1471)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
这里是 github link。如果有人能解决这个问题，那将非常有帮助。
【问题讨论】：
标签： spring spring-boot pdf-generation thymeleaf wkhtmltopdf