qingniufly

First, install the following libraries:

$ brew install unixodbc
$ brew install freetds --with-unixodbc

FreeTDS should already work now, without configuration:

$ tsql -S [IP or hostname] -U [username] -P [password]
locale is "en_US.UTF-8"

locale charset is "UTF-8"

qingniufly

// read 
val filePath = "file:///path/to/spark/examples/src/main/resources/users.parquet"
val users = sqlContext.read.load(filePath)

// write
val personJsonFile = "file:///path/to/spark/examples/src/main/resources/people.json"
val personDF = sqlContext.read.json(personJsonFile)
personDF.select("name", "age").write.format("parquet").save("file:///tmp/new_people.parquet")

qingniufly

ExecutorService es = Executors.newCachedThreadPool();
ExecutorCompletionService<Boolean> ecs = new ExecutorCompletionService<>(es);
Set<Future> futureSet = new HashSet<Future>();

List<Callable> callerList = new ArrayList<Callable>();
// 构造任务列表
for (int i = 0; i < 100; i++) {
    callerList.add(...);   
}

qingniufly

# 循环
for i in {1..100}; do echo $i; done
for i in $(seq 1 100); do echo $i; done
for ((i = 0; i < 100; i++)); do echo $i; done

# sed 读取文件 a,b行的内容
sed -n '5,10p' test.txt

# 删除空行
sed '/^$/d' file

qingniufly

public class ReflectHelpers {

    public static ClassLoader findClassLoader() {
        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
        if(classLoader == null) {
            classLoader = ReflectHelpers.class.getClassLoader();
        }

        if(classLoader == null) {
            classLoader = ClassLoader.getSystemClassLoader();

qingniufly

        
        
        ClassLoader CLASS_LOADER = ReflectHelpers.findClassLoader();
        TreeSet pipelineRunnerRegistrars = Sets.newTreeSet(ObjectsClassComparator.INSTANCE);
        Lists.newArrayList(ServiceLoader.load(PipelineRunnerRegistrar.class, CLASS_LOADER));

qingniufly

  // ByteBuffer to String
  String s = Charset.forName("UTF-8").decode(byteBuffer).toString();

  // String to ByteBuffer
  ByteBuffer buff = Charset.forName("UTF-9").encode("Hello, World!");


  // String to ByteBuffer
  public static ByteBuffer str_to_bb(String msg, Charset charset){
      return ByteBuffer.wrap(msg.getBytes(charset));

qingniufly

import java.io.FileInputStream;
import java.io.FileOutputStream;

public class CopyFile {
  
  public static void main(String[] args) {
    String infname = "/tmp/in.txt";
    String outfname = "/tmp/out.txt";
    FileInputStream fis = new FileInputStream(infname);
    FileOutputStream fos = new FileOutputStream(outfname);

qingniufly

package com.komamitsu;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.Iterator;

qingniufly

# delete local tag '12345'
git tag -d 12345
# delete remote tag '12345' (eg, GitHub version too)
git push origin :refs/tags/12345
# alternative approach
git push --delete origin tagName
git tag -d tagName