Example usage for javax.servlet ReadListener ReadListener

Introduction

In this page you can find the example usage for javax.servlet ReadListener ReadListener.

Prototype

ReadListener

Source Link

Usage

From source file:be.solidx.hot.utils.IOUtils.java

public static Promise<byte[], Exception, Void> asyncRead(final HttpServletRequest req,
        final ExecutorService executorService, final ExecutorService promiseResolver) {

    final DeferredObject<byte[], Exception, Void> deferredObject = new DeferredObject<>();

    try {/*w w w.  j a  v  a  2  s  . c  om*/
        final ServletInputStream servletInputStream = req.getInputStream();

        servletInputStream.setReadListener(new ReadListener() {

            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            @Override
            public void onError(final Throwable t) {
                promiseResolver.execute(new Runnable() {
                    @Override
                    public void run() {
                        deferredObject.reject(new Exception(t));
                    }
                });
            }

            @Override
            public void onDataAvailable() throws IOException {
                executorService.execute(new Runnable() {
                    @Override
                    public void run() {
                        byte b[] = new byte[2048];
                        int len = 0;

                        try {
                            while (servletInputStream.isReady() && (len = servletInputStream.read(b)) != -1) {
                                baos.write(b, 0, len);
                            }
                        } catch (IOException e) {
                            LOGGER.error("", e);
                        }
                    }
                });
            }

            @Override
            public void onAllDataRead() throws IOException {
                promiseResolver.execute(new Runnable() {
                    @Override
                    public void run() {
                        deferredObject.resolve(baos.toByteArray());
                    }
                });
            }
        });
    } catch (final IOException e2) {
        promiseResolver.execute(new Runnable() {
            @Override
            public void run() {
                deferredObject.reject(new Exception(e2));
            }
        });

    } catch (final IllegalStateException exception) {
        promiseResolver.execute(new Runnable() {
            @Override
            public void run() {
                deferredObject.resolve("".getBytes());
            }
        });
    }

    //      executorService.execute(new Runnable() {
    //         @Override
    //         public void run() {
    //            final ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    //            try {
    //               IOUtils.toOutputStreamBuffered(req.getInputStream(), outputStream);
    //               promiseResolver.execute(new Runnable() {
    //                  @Override
    //                  public void run() {
    //                     deferredObject.resolve(outputStream.toByteArray());
    //                  }
    //               });
    //            } catch (final IOException e) {
    //               promiseResolver.execute(new Runnable() {
    //                  @Override
    //                  public void run() {
    //                     deferredObject.reject(e);
    //                  }
    //               });
    //            }
    //         }
    //      });

    return deferredObject.promise();
}

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From source file:org.synchronoss.cloud.nio.multipart.example.web.MultipartController.java

/**
 * <p> This is an example how the NIO Parser can be used in a plain Servlet 3.1 fashion.
 *
 * @param request The {@code HttpServletRequest}
 * @throws IOException if an IO exception happens
 *//*from w w w.  ja  va 2 s.c  o m*/
@RequestMapping(value = "/nio/multipart", method = RequestMethod.POST)
public @ResponseBody void nioMultipart(final HttpServletRequest request) throws IOException {

    assertRequestIsMultipart(request);

    final VerificationItems verificationItems = new VerificationItems();
    final AsyncContext asyncContext = switchRequestToAsyncIfNeeded(request);
    final ServletInputStream inputStream = request.getInputStream();
    final AtomicInteger synchronizer = new AtomicInteger(0);

    final NioMultipartParserListener listener = new NioMultipartParserListener() {

        Metadata metadata;

        @Override
        public void onPartFinished(final StreamStorage partBodyStreamStorage,
                final Map<String, List<String>> headersFromPart) {
            if (log.isInfoEnabled())
                log.info("PARSER LISTENER - onPartFinished");
            final String fieldName = MultipartUtils.getFieldName(headersFromPart);
            final ChecksumStreamStorage checksumPartStreams = getChecksumStreamStorageOrThrow(
                    partBodyStreamStorage);
            if (METADATA_FIELD_NAME.equals(fieldName)) {
                metadata = unmarshalMetadataOrThrow(checksumPartStreams);
            } else {
                VerificationItem verificationItem = buildVerificationItem(checksumPartStreams, fieldName);
                verificationItems.getVerificationItems().add(verificationItem);
            }
        }

        @Override
        public void onNestedPartStarted(final Map<String, List<String>> headersFromParentPart) {
            if (log.isInfoEnabled())
                log.info("PARSER LISTENER - onNestedPartStarted");
        }

        @Override
        public void onNestedPartFinished() {
            if (log.isInfoEnabled())
                log.info("PARSER LISTENER - onNestedPartFinished");
        }

        @Override
        public void onFormFieldPartFinished(String fieldName, String fieldValue,
                Map<String, List<String>> headersFromPart) {
            if (log.isInfoEnabled())
                log.info("PARSER LISTENER - onFormFieldPartFinished");
            if (METADATA_FIELD_NAME.equals(fieldName)) {
                metadata = unmarshalMetadataOrThrow(fieldValue);
            }
        }

        @Override
        public void onAllPartsFinished() {
            if (log.isInfoEnabled())
                log.info("PARSER LISTENER - onAllPartsFinished");
            processVerificationItems(verificationItems, metadata, true);
            sendResponseOrSkip(synchronizer, asyncContext, verificationItems);
        }

        @Override
        public void onError(String message, Throwable cause) {
            // Probably invalid data...
            throw new IllegalStateException("Encountered an error during the parsing: " + message, cause);
        }

        synchronized Metadata unmarshalMetadataOrThrow(final String json) {
            if (metadata != null) {
                throw new IllegalStateException("Found two metadata fields");
            }
            return unmarshalMetadata(json);
        }

        synchronized Metadata unmarshalMetadataOrThrow(final ChecksumStreamStorage checksumPartStreams) {
            if (metadata != null) {
                throw new IllegalStateException("Found more than one metadata fields");
            }
            return unmarshalMetadata(checksumPartStreams.getInputStream());
        }

    };

    final MultipartContext ctx = getMultipartContext(request);
    final NioMultipartParser parser = multipart(ctx)
            .usePartBodyStreamStorageFactory(partBodyStreamStorageFactory).forNIO(listener);

    // Add a listener to ensure the parser is closed.
    asyncContext.addListener(new AsyncListener() {
        @Override
        public void onComplete(AsyncEvent event) throws IOException {
            parser.close();
        }

        @Override
        public void onTimeout(AsyncEvent event) throws IOException {
            parser.close();
        }

        @Override
        public void onError(AsyncEvent event) throws IOException {
            parser.close();
        }

        @Override
        public void onStartAsync(AsyncEvent event) throws IOException {
            // Nothing to do.
        }
    });

    inputStream.setReadListener(new ReadListener() {

        @Override
        public void onDataAvailable() throws IOException {
            if (log.isInfoEnabled())
                log.info("NIO READ LISTENER - onDataAvailable");
            int bytesRead;
            byte bytes[] = new byte[2048];
            while (inputStream.isReady() && (bytesRead = inputStream.read(bytes)) != -1) {
                parser.write(bytes, 0, bytesRead);
            }
            if (log.isInfoEnabled())
                log.info("Epilogue bytes...");
        }

        @Override
        public void onAllDataRead() throws IOException {
            if (log.isInfoEnabled())
                log.info("NIO READ LISTENER - onAllDataRead");
            sendResponseOrSkip(synchronizer, asyncContext, verificationItems);
        }

        @Override
        public void onError(Throwable throwable) {
            log.error("onError", throwable);
            IOUtils.closeQuietly(parser);
            sendErrorOrSkip(synchronizer, asyncContext, "Unknown error");
        }
    });

}

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