Example usage for com.fasterxml.jackson.databind MappingIterator getCurrentLocation

Introduction

In this page you can find the example usage for com.fasterxml.jackson.databind MappingIterator getCurrentLocation.

Prototype

public JsonLocation getCurrentLocation() 

Source Link

Document

Convenience method, functionally equivalent to: iterator.getParser().getCurrentLocation()

Usage

From source file:com.github.fge.jackson.JsonNodeReader.java

private static JsonNode readNode(final MappingIterator<JsonNode> iterator) throws IOException {
    final Object source = iterator.getParser().getInputSource();
    final JsonParseExceptionBuilder builder = new JsonParseExceptionBuilder(source);

    builder.setMessage(BUNDLE.getMessage("read.noContent"));

    if (!iterator.hasNextValue())
        throw builder.build();

    final JsonNode ret = iterator.nextValue();

    builder.setMessage(BUNDLE.getMessage("read.trailingData")).setLocation(iterator.getCurrentLocation());

    try {//from w  ww  .ja v  a2  s .  c  o m
        if (iterator.hasNextValue())
            throw builder.build();
    } catch (JsonParseException e) {
        throw builder.setLocation(e.getLocation()).build();
    }

    return ret;
}

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From source file:com.datafibers.kafka.connect.SchemaedFileSourceTask.java

private List<SourceRecord> pollFromFile() throws InterruptedException {
    log.trace("pollFromFile");
    CsvSchema bootstrapCsv;//from  ww  w  .  j a  v a 2s .c  o m
    CsvMapper csvMapper = new CsvMapper();
    ObjectMapper jsonMapper = new ObjectMapper();
    MappingIterator<Map<?, ?>> mappingIterator;
    ArrayList<SourceRecord> records = null;
    long currentTime = System.currentTimeMillis();
    long recordsPerPoll;

    // TODO: Improve ExceptionOnEof logic.
    // The code below only works when each pass through
    // poll() reads all available records (not a given).
    if (config.getExceptionOnEof() && streamOffset != null) {
        throw new ConnectException("No more deta available on FileInputStream");
    }

    // Initialize the bootstrapCsv schema if necessary
    if (recordSchema == null || inputType.equalsIgnoreCase("json")) {
        log.trace("Constructing csvSchema from emptySchema");
        bootstrapCsv = config.getCsvHeaders() ? CsvSchema.emptySchema().withHeader()
                : CsvSchema.emptySchema().withoutHeader();
    } else {
        // We've seen a schema, so we'll assume headers from the recordSchema
        log.trace("Constructing csvSchema from recordSchema");
        CsvSchema.Builder builder = new CsvSchema.Builder();
        builder.setUseHeader(false);
        builder.setColumnSeparator(',');
        for (Field f : recordSchema.fields()) {
            log.trace("adding column {}", f.name());
            builder.addColumn(f.name());
        }
        bootstrapCsv = builder.build();
    }
    try {
        if (stream == null)
            openFileStream();
        if (reader == null)
            reader = new BufferedReader(new InputStreamReader(stream));

        if (inputType.equalsIgnoreCase("json")) {
            mappingIterator = jsonMapper.readerFor(Map.class).readValues(reader);
        } else if (inputType.equalsIgnoreCase("csv")) {
            mappingIterator = csvMapper.readerWithSchemaFor(Map.class).with(bootstrapCsv).readValues(reader);
        } else {
            log.error("Unsupported file input type specified ({})", inputType);
            return null;
        }
    } catch (FileNotFoundException fnf) {
        log.warn("Couldn't find file {} for SchemaedFileSourceTask, sleeping to wait for it to be created",
                logFilename());
        synchronized (this) {
            this.wait(1000);
        }
        return null;
    } catch (IOException e) {
        // IOException thrown when no more records in stream
        log.warn("Processed all available data from {}; sleeping to wait additional records", logFilename());
        // Close reader and stream; swallowing exceptions ... we're about to throw a Retry
        try {
            reader.close();
        } catch (Exception nested) {
        } finally {
            reader = null;
        }

        if (stream != System.in) {
            try {
                stream.close();
            } catch (Exception nested) {
            } finally {
                stream = null;
            }
        }

        synchronized (this) {
            this.wait(1000);
        }
        return null;
    }
    log.debug("mappingIterator of type {} created; begin reading data file",
            mappingIterator.getClass().toString());

    // The csvMapper class is really screwy; can't figure out why it
    // won't return a rational Schema ... so we'll extract it from the
    // the first object later.
    if (recordSchema == null && inputType.equalsIgnoreCase("csv") && csvMapper.schema().size() > 0) {
        recordSchema = ConvertMappingSchema(csvMapper.schemaWithHeader());
        log.trace("recordSchema created from csvMapper; type {}", recordSchema.type().toString());
    }
    try {
        FileInputStream fstream = (FileInputStream) stream;
        Long lastElementOffset = streamOffset;
        recordsPerPoll = 3;

        while (mappingIterator.hasNext()) {
            Map<?, ?> element = mappingIterator.next();
            Long elementOffset, iteratorOffset;
            recordCount++;
            recordsPerPoll--;

            iteratorOffset = mappingIterator.getCurrentLocation().getByteOffset(); // never works !!!
            if (iteratorOffset < 0) {
                // The stream channel will CLOSE on the last clean record
                // seen by mapping Iterator, so we have be careful here
                // Additionally, when parsing CSV files, there seems to be a
                // lot of Bad File Descriptor errors; ignore them.
                try {
                    elementOffset = fstream.getChannel().position();
                } catch (java.nio.channels.ClosedChannelException e) {
                    log.trace("getChannel.position threw {}", e.toString());
                    elementOffset = lastElementOffset;
                } catch (IOException e) {
                    log.trace("getChannel.position threw {}", e.toString());
                    elementOffset = lastElementOffset;
                }
            } else {
                log.trace("mappingIterator.getCurrentLocation() returns {}", iteratorOffset.toString());
                elementOffset = iteratorOffset;
            }
            log.trace("Next input record: {} (class {}) from file position {}", element.toString(),
                    element.getClass().toString(), elementOffset.toString());

            if (recordSchema == null) {
                recordSchema = ConvertMappingSchema(element.keySet());
                log.trace("recordSchema created from element; type {}", recordSchema.type().toString());
            }

            if (records == null)
                records = new ArrayList<>();
            records.add(new SourceRecord(offsetKey(filename), offsetValue(elementOffset), topic, recordSchema,
                    ConvertMappingElement(recordSchema, (HashMap<?, ?>) element)));
            streamOffset = lastElementOffset = elementOffset;
        }
    } catch (Exception e) {
        throw new ConnectException(e);
    }

    lastPollTime = currentTime;
    return records;
}

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