Java DataFileReader.close方法代碼示例

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
/**
 * Reads in binary Avro-encoded entities using the schema stored in the file
 * and prints them out.
 */
public static void readAvroFile(File file) throws IOException {
	GenericDatumReader datum = new GenericDatumReader();
	DataFileReader reader = new DataFileReader(file, datum);

	GenericData.Record record = new GenericData.Record(reader.getSchema());
	while (reader.hasNext()) {
		reader.next(record);
		System.out.println("Name " + record.get("name") + " on "
				+ record.get("Meetup_date") + " attending "
				+ record.get("going") + " organized by  "
				+ record.get("organizer") + " on  " + record.get("topics"));
	}

	reader.close();
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
/**
 * 動態反序列：通過Schema文件進行動態反序列化操作
 * 
 * @throws IOException
 */
public void MemberInfoDynDeser() throws IOException {
    // 1.schema文件解析
    Parser parser = new Parser();
    Schema mSchema = parser.parse(this.getClass().getResourceAsStream("/Members.avsc"));

    // 2.構建數據讀對象
    DatumReader<GenericRecord> mGr = new SpecificDatumReader<GenericRecord>(mSchema);
    DataFileReader<GenericRecord> mDfr = new DataFileReader<GenericRecord>(new File("/Users/a/Desktop/tmp/members.avro"), mGr);
    // 3.從序列化文件中進行數據反序列化取出數據
    GenericRecord gr = null;
    while (mDfr.hasNext()) {
        gr = mDfr.next();
        System.err.println("deser data:" + gr.toString());
    }
    mDfr.close();
    System.out.println("Dyn Builder Ser Start Complete.");
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
/**
 * Reads in binary Avro-encoded entities using a schema that is different
 * from the writer's schema.
 * 
 */
public static void readWithDifferentSchema(File file, Schema newSchema)
		throws IOException {
	GenericDatumReader datum = new GenericDatumReader(newSchema);
	DataFileReader reader = new DataFileReader(file, datum);

	GenericData.Record record = new GenericData.Record(newSchema);
	while (reader.hasNext()) {
		reader.next(record);
		System.out.println("Name " + record.get("name") + " on "
				+ record.get("Meetup_date") + " attending "
				+ record.get("attendance") + " organized by  "
				+ record.get("organizer") 
				+ " at  " + record.get("location"));
	}

	reader.close();
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
@Override
public DatasetJsonRecord getSchema(Path targetFilePath)
  throws IOException {
  System.out.println("avro file path : " + targetFilePath.toUri().getPath());

  SeekableInput sin = new FsInput(targetFilePath, fs.getConf());
  DataFileReader<GenericRecord> reader =
    new DataFileReader<GenericRecord>(sin, new GenericDatumReader<GenericRecord>());
  String codec = reader.getMetaString("avro.codec");
  long record_count = reader.getBlockCount();

  String schemaString = reader.getSchema().toString();
  String storage = STORAGE_TYPE;
  String abstractPath = targetFilePath.toUri().getPath();

  FileStatus fstat = fs.getFileStatus(targetFilePath);
  DatasetJsonRecord datasetJsonRecord =
    new DatasetJsonRecord(schemaString, abstractPath, fstat.getModificationTime(), fstat.getOwner(), fstat.getGroup(),
      fstat.getPermission().toString(), codec, storage, "");
  reader.close();
  sin.close();
  return datasetJsonRecord;
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
public static Object deserializeFromByte(byte[] byteArray)
		throws IOException {
	SeekableByteArrayInput sin = new SeekableByteArrayInput(byteArray);
	System.out.println("length of read input stream " + sin.length());
	DatumReader<?> reader2 = new ReflectDatumReader<>();
	DataFileReader<?> in = new DataFileReader<>(sin, reader2);
	System.out.println(in.getSchema());
	System.out.println(in.hasNext());
	Object returnObject = null;
	System.out.println(in.getSchema().getFullName() );
	while (in.hasNext()) {
		returnObject = in.next();
		
	}
	in.close();
	return returnObject;
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
/**
 * @param file
 *            where to read from
 * @param schema
 *            Avro records structure
 * @return all values from the file
 * @throws IOException
 */
public static <T extends SpecificRecord> List<T> extractRecords(File file, Schema schema) throws IOException {
    DatumReader<T> reader = new SpecificDatumReader<>(schema);
    DataFileReader<T> fileReader = new DataFileReader<>(file, reader);
    List<T> data = new ArrayList<T>();
    try {
     while (fileReader.hasNext()) {
         data.add(fileReader.next());
     }
    } finally {
    	if(fileReader != null) {
    		fileReader.close();
    	}
    }
    return data;
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
private DataFileReader<T> getNextNonemptyReader() throws IOException {
	while (fileIterator != null && fileIterator.hasNext()) {
		LocatedFileStatus currentFileStatus = fileIterator.next();
		if (isValidFile(currentFileStatus)) {
			FileSystemPath currPath = new FileSystemPath(
					path.getFileSystem(), currentFileStatus.getPath());
			DataFileReader<T> reader = 
					getSingleFileReader(currPath, readerSchema);
			/** Check if the file contains at least one record */
			if(reader.hasNext()){
				return reader;
			} else {
				reader.close();
			}
		}
	}
	/** fallback */
	return null;
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
private void loadMembersToPurge(String filename) throws IOException
{
    // TODO: "memberId" column name should be configurable
    DataFileReader<GenericRecord> dataFileReader =
            createDataFileReader(filename, true);
    while (dataFileReader.hasNext())
    {
        GenericRecord record = dataFileReader.next();
        Integer memberId = (Integer) record.get("memberId");
        if (memberId == null)
        {
            throw new NullPointerException("memberId is null");
        }
        membersToPurge.add(((Number) record.get("memberId")).intValue());
    }
    dataFileReader.close();
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
private void testConversion(RestEntry<JsonObject> expected, WorkUnitState actualWorkUnitState) throws DataConversionException, IOException, JSONException {
  Schema schema = new Schema.Parser().parse(getClass().getResourceAsStream("/converter/nested.avsc"));
  GenericDatumReader<GenericRecord> datumReader = new GenericDatumReader<GenericRecord>(schema);

  File tmp = File.createTempFile(this.getClass().getSimpleName(), null);
  tmp.deleteOnExit();
  try {
    FileUtils.copyInputStreamToFile(getClass().getResourceAsStream("/converter/nested.avro"), tmp);
    DataFileReader<GenericRecord> dataFileReader = new DataFileReader<GenericRecord>(tmp, datumReader);
    GenericRecord avroRecord = dataFileReader.next();

    AvroToRestJsonEntryConverter converter = new AvroToRestJsonEntryConverter();
    RestEntry<JsonObject> actual = converter.convertRecord(null, avroRecord, actualWorkUnitState).iterator().next();

    Assert.assertEquals(actual.getResourcePath(), expected.getResourcePath());
    JSONAssert.assertEquals(expected.getRestEntryVal().toString(), actual.getRestEntryVal().toString(), false);

    converter.close();
    dataFileReader.close();
  } finally {
    if (tmp != null) {
      tmp.delete();
    }
  }
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
static <T> T runOnPreview(byte[] bits, AvroPreviewProcessor<T> processor) throws IOException {
  DatumReader<GenericRecord> datumReader = new GenericDatumReader<GenericRecord>();
  SeekableByteArrayInput sbai = new SeekableByteArrayInput(bits);
  DataFileReader<GenericRecord> dataFileReader = null;

  try {
    dataFileReader = new DataFileReader<>(sbai, datumReader);
    int headerLen = (int) dataFileReader.previousSync();
    byte[] header = Arrays.copyOf(bits, headerLen);
    if (dataFileReader.hasNext()) {
      GenericRecord gr = dataFileReader.next();
      return processor.process(header, gr, dataFileReader.getBlockCount(), dataFileReader.getBlockSize());
    } else {
      throw new RuntimeException("Empty Avro file - cannot run preview! ");
    }
  } finally {
    try { if (dataFileReader!=null) dataFileReader.close(); } catch (IOException safeToIgnore) {}
  }
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
public void validateAvroFile(File file) throws IOException {
  // read the events back using GenericRecord
  DatumReader<GenericRecord> reader = new GenericDatumReader<GenericRecord>();
  DataFileReader<GenericRecord> fileReader =
      new DataFileReader<GenericRecord>(file, reader);
  GenericRecord record = new GenericData.Record(fileReader.getSchema());
  int numEvents = 0;
  while (fileReader.hasNext()) {
    fileReader.next(record);
    String bodyStr = record.get("message").toString();
    System.out.println(bodyStr);
    numEvents++;
  }
  fileReader.close();
  Assert.assertEquals("Should have found a total of 3 events", 3, numEvents);
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
public List<Object> writeAvroFilesToStdout(Job job, Path outputPath) throws IOException {
    List<Object> records = new ArrayList<Object>();
    // Check that the results from the MapReduce were as expected.
    FileSystem fileSystem = FileSystem.get(job.getConfiguration());
    FileStatus[] outputFiles = fileSystem.globStatus(outputPath.suffix("/part-*"));
    Assert.assertEquals(1, outputFiles.length);
    DataFileReader<Object> reader = new DataFileReader<Object>(
            new FsInput(outputFiles[0].getPath(), job.getConfiguration()),
            new ReflectDatumReader<Object>());
    for (Object record : reader) {
        records.add(record);
        System.out.println(record);
    }
    reader.close();
    return records;
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
public void assertOutputResults(Job job, Path outputPath, Object[] expectedOutputs) throws IOException {
    List<Object> records = new ArrayList<Object>();
    // Check that the results from the MapReduce were as expected.
    FileSystem fileSystem = FileSystem.get(job.getConfiguration());
    FileStatus[] outputFiles = fileSystem.globStatus(outputPath.suffix("/part-*"));
    Assert.assertEquals(1, outputFiles.length);
    DataFileReader<Object> reader = new DataFileReader<Object>(
            new FsInput(outputFiles[0].getPath(), job.getConfiguration()),
            new ReflectDatumReader<Object>());
    for (Object record : reader) {
        records.add(record);
        System.out.println(record);
    }
    reader.close();

    assertArrayEquals(expectedOutputs, records.toArray());
}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
@Override
public DatasetJsonRecord getSchema(Path targetFilePath)
        throws IOException {
    LOG.info("avro file path : " + targetFilePath.toUri().getPath());
    try {
        SeekableInput sin = new FsInput(targetFilePath, fs.getConf());
        DataFileReader<GenericRecord> reader =
                new DataFileReader<GenericRecord>(sin, new GenericDatumReader<GenericRecord>());
        String codec = reader.getMetaString("avro.codec");
        long record_count = reader.getBlockCount();

        String schemaString = reader.getSchema().toString();
        String storage = STORAGE_TYPE;
        String abstractPath = targetFilePath.toUri().getPath();
        System.out.println("the schema string is: " + schemaString);
        System.out.println("the abstract path is: " + abstractPath);
      
        FileStatus fstat = fs.getFileStatus(targetFilePath);
        DatasetJsonRecord datasetJsonRecord =
                new DatasetJsonRecord(schemaString, abstractPath, fstat.getModificationTime(), fstat.getOwner(), fstat.getGroup(),
                        fstat.getPermission().toString(), codec, storage, "");
        reader.close();
        sin.close();
        LOG.info("Avro file datasetjsonrecorc get success, it is : " + datasetJsonRecord);
        return datasetJsonRecord;
    } catch (Exception e) {
        LOG.info("AvroAnalyzer get datasetjson failure, and exception is " + e.getMessage());
        return null;
    }

}
 

import org.apache.avro.file.DataFileReader; //導入方法依賴的package包/類
public void validateAvroFile(File file) throws IOException {
  // read the events back using GenericRecord
  DatumReader<GenericRecord> reader = new GenericDatumReader<GenericRecord>();
  DataFileReader<GenericRecord> fileReader =
      new DataFileReader<GenericRecord>(file, reader);
  GenericRecord record = new GenericData.Record(fileReader.getSchema());
  int numEvents = 0;
  while (fileReader.hasNext()) {
    fileReader.next(record);
    ByteBuffer body = (ByteBuffer) record.get("body");
    CharsetDecoder decoder = Charsets.UTF_8.newDecoder();
    String bodyStr = decoder.decode(body).toString();
    System.out.println(bodyStr);
    numEvents++;
  }
  fileReader.close();
  Assert.assertEquals("Should have found a total of 3 events", 3, numEvents);
}