Java FileWriteMode类代码示例

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
public static void writeFile(String fileName, String message){
    try {
        CharSink charSink = Files.asCharSink(new File(fileName), Charsets.UTF_8, FileWriteMode.APPEND);
        charSink.write(message + "\n");
    }catch(Exception e){

    }
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
private void extractOnlyOneTable(KeyspaceMetadata keyspace) throws Exception {
    File file = FileUtils.verify(filePath, force);

    if (!noddl) {
        System.out.println("Write \"" + tableName + "\" DDL to " + file.getCanonicalPath());
        Files.asCharSink(file, Charset.defaultCharset(), FileWriteMode.APPEND)
             .write(TableExporter.genDDL(keyspace.getTable(tableName)));
    }
    if (!nodml) {
        TableExporter.genDML(this, keyspace.getTable(tableName), file);
    }
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
@Test
public void givenUsingGuava_whenWritingReaderContentsToFile_thenCorrect() throws IOException {
	Reader initialReader = new StringReader("Some text");

	File targetFile = new File("src/test/resources/targetFile.txt");
	com.google.common.io.Files.touch(targetFile);
	CharSink charSink = com.google.common.io.Files.asCharSink(targetFile, Charset.defaultCharset(), FileWriteMode.APPEND);
	charSink.writeFrom(initialReader);

	initialReader.close();
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
private static void trueMain(final String[] args) throws IOException {
  final Parameters input = Parameters.loadSerifStyle(new File(args[0]));
  final String resolved = input.dump();
  final CharSink output = Files.asCharSink(new File(args[1]), Charsets.UTF_8,
      FileWriteMode.APPEND);
  output.write(resolved);
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
protected void updateMessagesReportFile(final LogMessageOccurence log) {
    try {
        final File file = getLogMessagesReportFile();
        file.getParentFile().mkdirs();
        Files.asCharSink(file, StandardCharsets.UTF_8, FileWriteMode.APPEND).write(log.toString() + "\n");
    } catch (IOException e) {
        LOG.error("Failed to append to file: {}", logMessagesReportFile.getPath(), e);
    }
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
/**
 * For multiple operations, you will need to store your data
 * <p>
 * Could have used temp.deleteOnExit();
 * </p>
 * <p>
 * Wont delete until jvm terminates. What if youre running in a webserver...
 * also has potential for memory leak
 * </p>
 */
@Test
public void needToStoreBetweenOperations() throws IOException {
  ByteSource from = Res.byteSource();
  File temp = File.createTempFile("partOne", ".xml");
  try {
    duplicateInput(from, Files.asByteSink(temp, FileWriteMode.APPEND));
    Processor.run(Files.asByteSource(temp), System.out);
  } finally {
    // dont expect this to run promptly (Effective Java - Item 7)
    temp.delete();
  }
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
@Test
public void downloadProductImage() throws Exception {
  when(productImageSeeker.seekProductImage(anyLong()))
      .thenReturn(Resources.getResource("Large_Scaled_Forest_Lizard.jpg").openStream());

  AtomicBoolean completed = new AtomicBoolean(false);
  AtomicBoolean error = new AtomicBoolean(false);
  File imageFile = File.createTempFile("image", ".jpg");
  imageFile.deleteOnExit();
  Files.touch(imageFile);
  ByteSink byteSink = Files.asByteSink(imageFile, FileWriteMode.APPEND);
  StreamObserver<DataChunk> streamObserver = new StreamObserver<DataChunk>() {
    @Override
    public void onNext(DataChunk dataChunk) {
      try {
        byteSink.write(dataChunk.getData().toByteArray());
      } catch (IOException e) {
        log.error("error on write files", e);
        onError(e);
      }
    }

    @Override
    public void onError(Throwable t) {
      error.compareAndSet(false, true);
    }

    @Override
    public void onCompleted() {
      log.info("write image to {}", imageFile.getAbsoluteFile());
      completed.compareAndSet(false, true);
    }
  };
  stub.downloadProductImage(DownloadProductImageRequest.getDefaultInstance(), streamObserver);

  while (!completed.get() && !error.get()) {
    Thread.sleep(500);
  }

  assertThat(completed.get()).isTrue();
  assertThat(error.get()).isFalse();

  try (InputStream destImageStream = new FileInputStream(imageFile);
       InputStream origImageStream = Resources.getResource("Large_Scaled_Forest_Lizard.jpg").openStream()) {
    assertThat(DigestUtils.md5Hex(destImageStream)).isEqualTo(
        DigestUtils.md5Hex(origImageStream)
    );
  }
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
public void write(Object o, File file, FileWriteMode... modes) {
    write(o, Files.asByteSink(file, modes));
}
 

import com.google.common.io.FileWriteMode; //导入依赖的package包/类
static void genDML(SchemaExporter generator, TableMetadata table, File file) throws IOException, ExecutionException, InterruptedException {
    String   tableName    = Utils.escapeReservedWord(table.getName());
    String   keyspaceName = table.getKeyspace().getName();
    CharSink charSink     = Files.asCharSink(file, Charset.defaultCharset(), FileWriteMode.APPEND);

    System.out.printf("-----------------------------------------------" + Main.LINE_SEPARATOR);
    System.out.printf("Extract from %s.%s" + Main.LINE_SEPARATOR, keyspaceName, tableName);

    if (generator.truncate) {
        charSink.write(QueryBuilder.truncate(keyspaceName, tableName).getQueryString());
    }

    Row firstRow = getFirstRow(generator.session, tableName, keyspaceName);

    if (firstRow == null) {
        return;
    }

    final List<String>                 colNames    = new ArrayList();
    final List<TypeCodec>              typeCodecs  = new ArrayList();
    List<ColumnDefinitions.Definition> definitions = firstRow.getColumnDefinitions().asList();

    for (ColumnDefinitions.Definition definition : definitions) {
        String   colName = definition.getName();
        DataType type    = definition.getType();
        colNames.add(Utils.escapeReservedWord(colName));
        Object object = firstRow.getObject(colName);
        typeCodecs.add(object != null ? CODEC_REGISTRY.codecFor(type, object) : CODEC_REGISTRY
                .codecFor(type));
    }

    String prefix = "INSERT INTO " + keyspaceName + "." + tableName + " (" + Joiner.on(',')
                                                                                   .join(colNames) + ") VALUES (";
    String postfix = generator.merge ? ") IF NOT EXISTS;" : ");";

    long totalNoOfRows = getTotalNoOfRows(generator.session, tableName, keyspaceName);
    System.out.printf("Total number of record: %s" + Main.LINE_SEPARATOR, totalNoOfRows);

    int count = 0;
    Select select = QueryBuilder.select()
                                .all()
                                .from(keyspaceName, tableName).allowFiltering();
    select.setFetchSize(SchemaExporter.FETCH_SIZE);
    ResultSet     resultSet = generator.session.execute(select);
    Iterator<Row> iterator  = resultSet.iterator();

    System.out.printf("Start write \"%s\" data DML to %s" + Main.LINE_SEPARATOR, tableName, file.getCanonicalPath());

    int  noOfStep  = getNoOfStep(totalNoOfRows);
    long step      = totalNoOfRows / noOfStep;
    int  stepCount = 0;

    while (iterator.hasNext()) {
        Row    next      = iterator.next();
        String statement = generateInsertFromRow(typeCodecs, prefix, postfix, next) + Main.LINE_SEPARATOR;
        charSink.write(statement);
        count++;
        if (totalNoOfRows > SchemaExporter.FETCH_SIZE && count > stepCount * step) {
            float v = (float) count / (float) totalNoOfRows * 100;
            System.out.printf("Done %.2f%%" + Main.LINE_SEPARATOR, v);
            stepCount++;
        }
    }
    System.out.printf("Done exporting \"%s\", total number of records exported: %s" + Main.LINE_SEPARATOR, tableName, count);
}