我的Restlet资源出现问题。它使用TrueZip构建Zip存档的子集,并允许用户下载它。
// Create a Streaming Response Entity.
final StreamingOutput stream = new StreamingOutput() {
@Override
public void write(final OutputStream output) {
ZipBrowser.extract(source, path, output);
}
};
LOGGER.debug("Download of Path {} with the length {} initiated", path, length);
ResponseBuilder rb = Response.ok(stream);
rb.header(HeaderConstants.HEADER_CONTENT_DISPOSITION, CONDISPOVALUE + fileName);
rb.header(HeaderConstants.HEADER_CONTENT_LENGTH, length);
return rb.build();
即使它工作,我收到恼人的StreamClosedException。仅当我尝试下载子集而不是整个Zip存档时才会出现此错误:
An exception occured writing the responseentity
sun.net.httpserver.StreamClosedException
at sun.net.httpserver.ChunkedOutputStream.flush(ChunkedOutputStream.java:156)
at sun.net.httpserver.PlaceholderOutputStream.flush(ExchangeImpl.java:449)
at org.restlet.engine.adapter.ServerCall.writeResponseBody(ServerCall.java:511)
at org.restlet.engine.adapter.ServerCall.sendResponse(ServerCall.java:454)
at org.restlet.engine.adapter.ServerAdapter.commit(ServerAdapter.java:187)
at org.restlet.engine.adapter.HttpServerHelper.handle(HttpServerHelper.java:144)
at org.restlet.engine.connector.HttpServerHelper$1.handle(HttpServerHelper.java:64)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:77)
at sun.net.httpserver.AuthFilter.doFilter(AuthFilter.java:83)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:80)
at sun.net.httpserver.ServerImpl$Exchange$LinkHandler.handle(ServerImpl.java:677)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:77)
at sun.net.httpserver.ServerImpl$Exchange.run(ServerImpl.java:649)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)Unable to send error response
java.io.IOException: headers already sent
at sun.net.httpserver.ExchangeImpl.sendResponseHeaders(ExchangeImpl.java:204)
at sun.net.httpserver.HttpExchangeImpl.sendResponseHeaders(HttpExchangeImpl.java:86)
at org.restlet.engine.connector.HttpExchangeCall.writeResponseHead(HttpExchangeCall.java:148)
at org.restlet.engine.adapter.ServerCall.sendResponse(ServerCall.java:450)
at org.restlet.engine.adapter.ServerAdapter.commit(ServerAdapter.java:205)
at org.restlet.engine.adapter.HttpServerHelper.handle(HttpServerHelper.java:144)
at org.restlet.engine.connector.HttpServerHelper$1.handle(HttpServerHelper.java:64)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:77)
at sun.net.httpserver.AuthFilter.doFilter(AuthFilter.java:83)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:80)
at sun.net.httpserver.ServerImpl$Exchange$LinkHandler.handle(ServerImpl.java:677)
at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:77)
at sun.net.httpserver.ServerImpl$Exchange.run(ServerImpl.java:649)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
答案 0 :(得分:2)
这是由zip库和Restlet Framework在完成后尝试关闭OutputStream
引起的。
我过去经历过这个与其他库的比较,并设法通过将OutputStream
传递给一个覆盖close()
无法执行任何操作的类中的zip库来消除异常。委托所有其他方法。然后,这允许Restlet关闭流。
因此,代码中调用Zip实用程序的行变为:
ZipBrowser.extract(source, path, new WrappedOutputStream(output));
下面指出了WrappedOutputStream
类(需要添加委托方法)。
import java.io.IOException;
import java.io.OutputStream;
public class WrappedOutputStream extends OutputStream {
private final OutputStream delegate;
public WrappedOutputStream(final OutputStream delegate) {
this.delegate = delegate;
}
public void close() throws IOException {
// Do Nothing to allow Restlet to close the underlying stream
}
// TODO Delegate other Outpt Stream methods.
}