shell复制代码# 加上以下的这两个参数即可开启对应的JFR功能
java -XX:+UnlockCommercialFeatures -XX:+FlightRecorder

shell复制代码jcmd process_id VM.unlock_commercial_features 解锁JFR记录功能权限

shell复制代码jcmd激活 jcmd process_id JFR.start duration=100s filename=flight.jfr （JDK 11版本前需要先激活对应的功能）

shell复制代码jcmd 5361 help JFR.check

# 命令行返回值
5361:
JFR.check
Checks running JFR recording(s)

Impact: Low

Permission: java.lang.management.ManagementPermission(monitor)

Syntax : JFR.check [options]

Options: (options must be specified using the <key> or <key>=<value> syntax)
	name : [optional] Recording name, e.g. \"My Recording\" or omit to see all recordings (STRING, no default value)
	recording : [optional] Recording number, or omit to see all recordings (JLONG, -1)
	verbose : [optional] Print event settings for the recording(s) (BOOLEAN, false)

java复制代码public static void main(String[] args) {
    List<Object> items = new ArrayList<>(1);
    try {
        while (true){
            items.add(new Object());
        }
    } catch (OutOfMemoryError e){
        System.out.println(e.getMessage());
    }
    assert items.size() > 0;
    try {
        Thread.sleep(1000);
    } catch (InterruptedException e) {
        System.out.println(e.getMessage());
    }
}

java复制代码java -XX:+UnlockCommercialFeatures -XX:+FlightRecorder 
  -XX:StartFlightRecording=duration=200s,filename=flight.jfr

sh复制代码code path/to/file

sh复制代码Could not open App.vue in the editor.

To specify an editor, specify the EDITOR env variable or add "editor" field to your Vue project config.

sh复制代码# .env.development
# 当然，我的命令行终端已经有了code这个命令。
EDITOR=code

sh复制代码Vue CLI 3 supports this feature out-of-the-box when running vue-cli-service serve.

sh复制代码# 1. Import the package:
var openInEditor = require('launch-editor-middleware')
# 2. In the devServer option, register the /__open-in-editor HTTP route:
devServer: {
  before (app) {
    app.use('/__open-in-editor', openInEditor())
  }
}
# 3. The editor to launch is guessed. You can also specify the editor app with the editor option. See the supported editors list.
# 用哪个编辑器打开会自动猜测。你也可以具体指明编辑器。这里显示更多的支持编辑器列表
openInEditor('code')
# 4. You can now click on the name of the component in the Component inspector pane (if the devtools knows about its file source, a tooltip will appear).
# 如果`vue-devtools`开发者工具有提示点击的组件的显示具体路径，那么你可以在编辑器打开。

sh复制代码npm install -g @vue/cli
# OR
yarn global add @vue/cli

sh复制代码node -V
# v14.16.0
vue -V 
# @vue/cli 4.5.12
vue create vue3-project
# 这里选择的是vue3、vue2也是一样的。
# Please pick a preset: Default (Vue 3 Preview) ([Vue 3] babel, eslint)
npm install
# OR
yarn install

sh复制代码code -v
1.55.2

js复制代码// vue3-project/node_modules/@vue/cli-service/lib/commands/serve.js
// 46行
const launchEditorMiddleware = require('launch-editor-middleware')
// 192行
before (app, server) {
    // launch editor support.
    // this works with vue-devtools & @vue/cli-overlay
    app.use('/__open-in-editor', launchEditorMiddleware(() => console.log(
        `To specify an editor, specify the EDITOR env variable or ` +
        `add "editor" field to your Vue project config.\n`
    )))
    // 省略若干代码...
}

js复制代码// vue3-project/node_modules/launch-editor-middleware/index.js
const url = require('url')
const path = require('path')
const launch = require('launch-editor')

module.exports = (specifiedEditor, srcRoot, onErrorCallback) => {
  // specifiedEditor => 这里传递过来的则是 () => console.log() 函数
  // 所以和 onErrorCallback 切换下，把它赋值给错误回调函数
  if (typeof specifiedEditor === 'function') {
    onErrorCallback = specifiedEditor
    specifiedEditor = undefined
  }

  // 如果第二个参数是函数，同样把它赋值给错误回调函数
  // 这里传递过来的是undefined
  if (typeof srcRoot === 'function') {
    onErrorCallback = srcRoot
    srcRoot = undefined
  }

  // srcRoot 是传递过来的参数，或者当前node进程的目录
  srcRoot = srcRoot || process.cwd()

  // 最后返回一个函数， express 中间件
  return function launchEditorMiddleware (req, res, next) {
    // 省略 ...
  }
}

js复制代码// vue3-project/node_modules/launch-editor-middleware/index.js
module.exports = (specifiedEditor, srcRoot, onErrorCallback) => {
  // 省略上半部分
  return function launchEditorMiddleware (req, res, next) {
    // 根据请求解析出file路径
    const { file } = url.parse(req.url, true).query || {}
    // 如果没有文件路径，则报错
    if (!file) {
      res.statusCode = 500
      res.end(`launch-editor-middleware: required query param "file" is missing.`)
    } else {
      // 否则拼接路径，用launch打开。
      launch(path.resolve(srcRoot, file), specifiedEditor, onErrorCallback)
      res.end()
    }
  }
}

js复制代码// vue3-project/node_modules/launch-editor/index.js
function launchEditor (file, specifiedEditor, onErrorCallback) {
  // 解析出文件路径和行号列号等信息
  const parsed = parseFile(file)
  let { fileName } = parsed
  const { lineNumber, columnNumber } = parsed

  // 判断文件是否存在，不存在，直接返回。
  if (!fs.existsSync(fileName)) {
    return
  }
  // 所以和 onErrorCallback 切换下，把它赋值给错误回调函数
  if (typeof specifiedEditor === 'function') {
    onErrorCallback = specifiedEditor
    specifiedEditor = undefined
  }
  // 包裹一层函数
  onErrorCallback = wrapErrorCallback(onErrorCallback)

  // 猜测当前进程运行的是哪个编辑器
  const [editor, ...args] = guessEditor(specifiedEditor)
  if (!editor) {
    onErrorCallback(fileName, null)
    return
  }
  // 省略剩余部分，后文再讲述...
}

js复制代码onErrorCallback = wrapErrorCallback(onErrorCallback)

js复制代码// vue3-project/node_modules/launch-editor/index.js
function wrapErrorCallback (cb) {
  return (fileName, errorMessage) => {
    console.log()
    console.log(
      chalk.red('Could not open ' + path.basename(fileName) + ' in the editor.')
    )
    if (errorMessage) {
      if (errorMessage[errorMessage.length - 1] !== '.') {
        errorMessage += '.'
      }
      console.log(
        chalk.red('The editor process exited with an error: ' + errorMessage)
      )
    }
    console.log()
    if (cb) cb(fileName, errorMessage)
  }
}

js复制代码const [editor, ...args] = guessEditor(specifiedEditor)
if (!editor) {
    onErrorCallback(fileName, null)
    return
}

js复制代码// vue3-project/node_modules/launch-editor/guess.js
const shellQuote = require('shell-quote')
const childProcess = require('child_process')

module.exports = function guessEditor (specifiedEditor) {
  // 如果指定了编辑器，则解析一下，这里没有传入。如果自己指定了路径。
  // 比如 c/Users/lxchu/AppData/Local/Programs/Microsoft VS Code/bin/code 
  //   会根据空格切割成 c/Users/lxchu/AppData/Local/Programs/Microsoft
  if (specifiedEditor) {
    return shellQuote.parse(specifiedEditor)
  }
  // We can find out which editor is currently running by:
  // `ps x` on macOS and Linux
  // `Get-Process` on Windows
  try {
    //  代码有删减
    if (process.platform === 'darwin') {
      const output = childProcess.execSync('ps x').toString()
      // 省略
    } else if (process.platform === 'win32') {
      const output = childProcess
        .execSync('powershell -Command "Get-Process | Select-Object Path"', {
          stdio: ['pipe', 'pipe', 'ignore']
        })
        .toString()
        // 省略
    } else if (process.platform === 'linux') {
      const output = childProcess
        .execSync('ps x --no-heading -o comm --sort=comm')
        .toString()
    }
  } catch (error) {
    // Ignore...
  }

  // Last resort, use old skool env vars
  if (process.env.VISUAL) {
    return [process.env.VISUAL]
  } else if (process.env.EDITOR) {
    return [process.env.EDITOR]
  }

  return [null]
}

js复制代码// vue3-project/node_modules/launch-editor/index.js
function launchEditor(){
  //  省略上部分...
  if (
    process.platform === 'linux' &&
    fileName.startsWith('/mnt/') &&
    /Microsoft/i.test(os.release())
  ) {
    // Assume WSL / "Bash on Ubuntu on Windows" is being used, and
    // that the file exists on the Windows file system.
    // `os.release()` is "4.4.0-43-Microsoft" in the current release
    // build of WSL, see: https://github.com/Microsoft/BashOnWindows/issues/423#issuecomment-221627364
    // When a Windows editor is specified, interop functionality can
    // handle the path translation, but only if a relative path is used.
    fileName = path.relative('', fileName)
  }

  if (lineNumber) {
    const extraArgs = getArgumentsForPosition(editor, fileName, lineNumber, columnNumber)
    args.push.apply(args, extraArgs)
  } else {
    args.push(fileName)
  }

  if (_childProcess && isTerminalEditor(editor)) {
    // There's an existing editor process already and it's attached
    // to the terminal, so go kill it. Otherwise two separate editor
    // instances attach to the stdin/stdout which gets confusing.
    _childProcess.kill('SIGKILL')
  }

  if (process.platform === 'win32') {
    // On Windows, launch the editor in a shell because spawn can only
    // launch .exe files.
    _childProcess = childProcess.spawn(
      'cmd.exe',
      ['/C', editor].concat(args),
      { stdio: 'inherit' }
    )
  } else {
    _childProcess = childProcess.spawn(editor, args, { stdio: 'inherit' })
  }
  _childProcess.on('exit', function (errorCode) {
    _childProcess = null

    if (errorCode) {
      onErrorCallback(fileName, '(code ' + errorCode + ')')
    }
  })

  _childProcess.on('error', function (error) {
    onErrorCallback(fileName, error.message)
  })
}

js复制代码const childProcess = require('child_process')

if (process.platform === 'win32') {
    // On Windows, launch the editor in a shell because spawn can only
    // launch .exe files.
    _childProcess = childProcess.spawn(
        'cmd.exe',
        ['/C', editor].concat(args),
        { stdio: 'inherit' }
    )
    } else {
    _childProcess = childProcess.spawn(editor, args, { stdio: 'inherit' })
}

sh复制代码code path/to/file

java复制代码private ThreadLocal<Integer> localInt = new ThreadLocal<>();

java复制代码public int setAndGet(){
    localInt.set(8);
    return localInt.get();
}

java复制代码private ThreadLocal<Integer> localInt = ThreadLocal.withInitial(() -> 6);

java复制代码public T get() {
    //获得当前线程
    Thread t = Thread.currentThread();
    //每个线程 都有一个自己的ThreadLocalMap，
    //ThreadLocalMap里就保存着所有的ThreadLocal变量
    ThreadLocalMap map = getMap(t);
    if (map != null) {
        //ThreadLocalMap的key就是当前ThreadLocal对象实例，
        //多个ThreadLocal变量都是放在这个map中的
        ThreadLocalMap.Entry e = map.getEntry(this);
        if (e != null) {
            @SuppressWarnings("unchecked")
            //从map里取出来的值就是我们需要的这个ThreadLocal变量
            T result = (T)e.value;
            return result;
        }
    }
    // 如果map没有初始化，那么在这里初始化一下
    return setInitialValue();
}

java复制代码ThreadLocal.ThreadLocalMap threadLocals = null;

java复制代码static class Entry extends WeakReference<ThreadLocal<?>> {
    /** The value associated with this ThreadLocal. */
    Object value;
    //key就是一个弱引用
    Entry(ThreadLocal<?> k, Object v) {
        super(k);
        value = v;
    }
}

java复制代码private Entry getEntry(ThreadLocal<?> key) {
    int i = key.threadLocalHashCode & (table.length - 1);
    Entry e = table[i];
    if (e != null && e.get() == key)
        //如果找到key，直接返回
        return e;
    else
        //如果找不到，就会尝试清理，如果你总是访问存在的key，那么这个清理永远不会进来
        return getEntryAfterMiss(key, i, e);
}

java复制代码private Entry getEntryAfterMiss(ThreadLocal<?> key, int i, Entry e) {
    Entry[] tab = table;
    int len = tab.length;

    while (e != null) {
        // 整个e是entry ，也就是一个弱引用
        ThreadLocal<?> k = e.get();
        //如果找到了，就返回
        if (k == key)
            return e;
        if (k == null)
            //如果key为null，说明弱引用已经被回收了
            //那么就要在这里回收里面的value了
            expungeStaleEntry(i);
        else
            //如果key不是要找的那个，那说明有hash冲突，这里是处理冲突，找下一个entry
            i = nextIndex(i, len);
        e = tab[i];
    }
    return null;
}

java复制代码public static void main(String[] args) {
    ThreadLocal threadLocal = new ThreadLocal();
    IntStream.range(0,10).forEach(i -> {
        //每个线程的序列号，希望在子线程中能够拿到
        threadLocal.set(i);
        //这里来了一个子线程，我们希望可以访问上面的threadLocal
        new Thread(() -> {
            System.out.println(Thread.currentThread().getName() + ":" + threadLocal.get());
        }).start();
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    });
}

java复制代码Thread-0:null
Thread-1:null
Thread-2:null
Thread-3:null

java复制代码InheritableThreadLocal threadLocal = new InheritableThreadLocal();

java复制代码Thread-0:0
Thread-1:1
Thread-2:2
Thread-3:3
Thread-4:4

java复制代码class Wait_Notify_ACB {

    private int num;
    private static final Object LOCK = new Object();

    private void printABC(int targetNum) {
            synchronized (LOCK) {
                while (num % 3 != targetNum) {    //想想这里为什么不能用if代替while，想不起来可以看公众号上一篇文章
                    try {
                        LOCK.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                num++;
                System.out.print(Thread.currentThread().getName());
                LOCK.notifyAll();
            }
    }
    
    public static void main(String[] args) {
        Wait_Notify_ACB  wait_notify_acb = new Wait_Notify_ACB ();
        new Thread(() -> {
            wait_notify_acb.printABC(0);
        }, "A").start();
        new Thread(() -> {
            wait_notify_acb.printABC(1);
        }, "B").start();
        new Thread(() -> {
            wait_notify_acb.printABC(2);
        }, "C").start();
    }
}

java复制代码ABC
Process finished with exit code 0

java复制代码class Wait_Notify_ACB {

    private int num;
    private static final Object LOCK = new Object();

    private void printABC(int targetNum) {
        for (int i = 0; i < 10; i++) {
            synchronized (LOCK) {
                while (num % 3 != targetNum) { //想想这里为什么不能用if代替，想不起来可以看公众号上一篇文章
                    try {
                        LOCK.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                num++;
                System.out.print(Thread.currentThread().getName());
                LOCK.notifyAll();
            }
        }
    }
    public static void main(String[] args) {
        Wait_Notify_ACB  wait_notify_acb = new Wait_Notify_ACB ();
        new Thread(() -> {
            wait_notify_acb.printABC(0);
        }, "A").start();
        new Thread(() -> {
            wait_notify_acb.printABC(1);
        }, "B").start();
        new Thread(() -> {
            wait_notify_acb.printABC(2);
        }, "C").start();
    }    
}

java复制代码ABCABCABCABCABCABCABCABCABCABC
Process finished with exit code 0

java复制代码class  Wait_Notify_Odd_Even{

    private Object monitor = new Object();
    private volatile int count;

    Wait_Notify_Odd_Even(int initCount) {
        this.count = initCount;
    }

    private void printOddEven() {
        synchronized (monitor) {
            while (count < 10) {
                try {
                    System.out.print( Thread.currentThread().getName() + "：");
                    System.out.println(++count);
                    monitor.notifyAll();
                    monitor.wait();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            //防止count=10后，while()循环不再执行，有子线程被阻塞未被唤醒，导致主线程不能退出
            monitor.notifyAll();
        }
    }
    
    public static void main(String[] args) throws InterruptedException {

        Wait_Notify_Odd_Even waitNotifyOddEven = new Wait_Notify_Odd_Even(0);
        new Thread(waitNotifyOddEven::printOddEven, "odd").start();
        Thread.sleep(10); //为了保证线程odd先拿到锁
        new Thread(waitNotifyOddEven::printOddEven, "even").start();
    }
}

java复制代码odd：1
even：2
odd：3
even：4
odd：5
even：6
odd：7
even：8
odd：9
even：10

java复制代码class Wait_Notify_100 {

    private int num;
    private static final Object LOCK = new Object();
    private int maxnum = 10;

    private void printABC(int targetNum) {
        while (true) {
            synchronized (LOCK) {
                while (num % 3 != targetNum) { //想想这里为什么不能用if代替，想不起来可以看公众号上一篇文章
                    if(num >= maxnum){
                        break;
                    }
                    try {
                        LOCK.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                if(num >= maxnum){
                    break;
                }
                num++;
                System.out.println(Thread.currentThread().getName() + ": " + num);
                LOCK.notifyAll();
            }
        }

    }
    
    public static void main(String[] args) {
        Wait_Notify_100  wait_notify_100 = new Wait_Notify_100 ();
        new Thread(() -> {
            wait_notify_100.printABC(0);
        }, "thread1").start();
        new Thread(() -> {
            wait_notify_100.printABC(1);
        }, "thread2").start();
        new Thread(() -> {
            wait_notify_100.printABC(2);
        }, "thread3").start();
    }    
}

java复制代码thread1: 1
thread2: 2
thread3: 3
thread1: 4
thread2: 5
thread3: 6
thread1: 7
thread2: 8
thread3: 9
thread1: 10

java复制代码class Join_ABC {

    public static void main(String[] args) throws InterruptedException {
        for (int i = 0; i < 10; i++) {
            Thread t1 = new Thread(new printABC(null),"A");
            Thread t2 = new Thread(new printABC(t1),"B");
            Thread t3 = new Thread(new printABC(t2),"C");
            t0.start();
            t1.start();
            t2.start();
            Thread.sleep(10); //这里是要保证只有t1、t2、t3为一组，进行执行才能保证t1->t2->t3的执行顺序。
        }

    }

    static class printABC implements Runnable{
        private Thread beforeThread;
        public printABC(Thread beforeThread) {
            this.beforeThread = beforeThread;
        }
        @Override
        public void run() {
            if(beforeThread!=null) {
                try {
                    beforeThread.join(); 
                    System.out.print(Thread.currentThread().getName());
                }catch(Exception e){
                    e.printStackTrace();
                }
            }else {
                System.out.print(Thread.currentThread().getName());
            }

        }
    }
}

java复制代码ABCABCABCABCABCABCABCABCABCABC

java复制代码 class Lock_ABC {

    private int num;   // 当前状态值：保证三个线程之间交替打印
    private Lock lock = new ReentrantLock();


    private void printABC(int targetNum) {
        for (int i = 0; i < 10; ) {
            lock.lock();
            if (num % 3 == targetNum) {
                num++;
                i++;
                System.out.print(Thread.currentThread().getName());
            }
            lock.unlock();
        }
    }

    public static void main(String[] args) {
        Lock_ABC lockABC = new Lock_ABC();

        new Thread(() -> {
            lockABC.printABC(0);
        }, "A").start();

        new Thread(() -> {
            lockABC.printABC(1);
        }, "B").start();

        new Thread(() -> {
            lockABC.printABC(2);
        }, "C").start();
    }
}

java复制代码ABCABCABCABCABCABCABCABCABCABC

java复制代码class LockConditionABC {

    private int num;
    private static Lock lock = new ReentrantLock();
    private static Condition c1 = lock.newCondition();
    private static Condition c2 = lock.newCondition();
    private static Condition c3 = lock.newCondition();

    private void printABC(int targetNum, Condition currentThread, Condition nextThread) {
        for (int i = 0; i < 10; ) {
            lock.lock();
            try {
                while (num % 3 != targetNum) {
                    currentThread.await();  //阻塞当前线程
                }
                num++;
                i++;
                System.out.print(Thread.currentThread().getName());
                nextThread.signal();    //唤醒下一个线程，而不是唤醒所有线程
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                lock.unlock();
            }
        }
    }

    public static void main(String[] args) {
        LockConditionABC print = new LockConditionABC();
        new Thread(() -> {
            print.printABC(0, c1, c2);
        }, "A").start();
        new Thread(() -> {
            print.printABC(1, c2, c3);
        }, "B").start();
        new Thread(() -> {
            print.printABC(2, c3, c1);
        }, "C").start();
    }
}

java复制代码ABCABCABCABCABCABCABCABCABCABC

java复制代码class SemaphoreABC {

    private static Semaphore s1 = new Semaphore(1); //因为先执行线程A，所以这里设s1的计数器为1
    private static Semaphore s2 = new Semaphore(0);
    private static Semaphore s3 = new Semaphore(0);


    private void printABC(Semaphore currentThread, Semaphore nextThread) {
        for (int i = 0; i < 10; i++) {
            try {
                currentThread.acquire();       //阻塞当前线程，即信号量的计数器减1为0
                System.out.print(Thread.currentThread().getName());
                nextThread.release();          //唤醒下一个线程，即信号量的计数器加1

            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) throws InterruptedException {
        SemaphoreABC printer = new SemaphoreABC();
        new Thread(() -> {
            printer.printABC(s1, s2);
        }, "A").start();
        Thread.sleep(10);
        new Thread(() -> {
            printer.printABC(s2, s3);
        }, "B").start();
        Thread.sleep(10);
        new Thread(() -> {
            printer.printABC(s3, s1);
        }, "C").start();
    }
}

java复制代码ABCABCABCABCABCABCABCABCABCABC

xml复制代码<dependencies>
    <dependency>
        <groupId>org.elasticsearch</groupId>
        <artifactId>elasticsearch</artifactId>
        <version>7.8.0</version>
    </dependency>
    <!-- elasticsearch的客户端 -->
    <dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>elasticsearch-rest-high-level-client</artifactId>
        <version>7.8.0</version>
    </dependency>
    <!-- elasticsearch依赖2.x的log4j -->
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-api</artifactId>
        <version>2.8.2</version>
    </dependency>
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-core</artifactId>
        <version>2.8.2</version>
</dependency>
	<dependency>
		<groupId>com.fasterxml.jackson.core</groupId>
		<artifactId>jackson-databind</artifactId>
		<version>2.9.9</version>
	</dependency>
    <!-- junit单元测试 -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>
</dependencies>

makefile复制代码java.lang.NoSuchMethodError: org.elasticsearch.client.Request.addParameters

java复制代码public static void main(String[] args) throws IOException {
    RestHighLevelClient esClient = new RestHighLevelClient(
        RestClient.builder(new HttpHost("localhost", 9200, "http"))
    );

    esClient.close();
}

java复制代码RestHighLevelClient esClient = new RestHighLevelClient(
    RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
@Test
public void index_create() throws IOException {
    // 创建索引 - 请求对象
    CreateIndexRequest request = new CreateIndexRequest("test");
    // 发送请求，获取响应
    CreateIndexResponse response = esClient.indices().create(request, RequestOptions.DEFAULT);
    boolean acknowledged = response.isAcknowledged();
    // 响应状态
    System.out.println("操作状态 = " + acknowledged);
}

java复制代码RestHighLevelClient esClient = new RestHighLevelClient(
    RestClient.builder(new HttpHost("localhost", 9200, "http"))
);

@Test
public void index_get() throws IOException {

    GetIndexRequest request = new GetIndexRequest("test");

    GetIndexResponse response = esClient.indices().get(request, RequestOptions.DEFAULT);

    System.out.println(Arrays.toString(response.getIndices()));
    System.out.println(response.getMappings());
    System.out.println(response.getSettings());
}

java复制代码RestHighLevelClient esClient = new RestHighLevelClient(
    RestClient.builder(new HttpHost("localhost", 9200, "http"))
);

@Test
public void index_delete() throws IOException {

    DeleteIndexRequest request = new DeleteIndexRequest("test");

    AcknowledgedResponse response = esClient.indices().delete(request, RequestOptions.DEFAULT);

    System.out.println(response.isAcknowledged());
}

java复制代码@Test
public void doc_create() throws IOException {
    IndexRequest request = new IndexRequest();
    // 设置操作的索引和当前插入的文档的id
    request.index("people").id("1001");

    User user = new User();
    user.setName("张三");
    user.setAge(10);
    user.setSex("男");

    ObjectMapper mapper = new ObjectMapper();
    String userJson = mapper.writeValueAsString(user);

    request.source(userJson, XContentType.JSON);

    IndexResponse response = esClient.index(request, RequestOptions.DEFAULT);

    System.out.println(response);

    System.out.println("_index" + response.getIndex());
    System.out.println("_id" + response.getId());
    System.out.println("_result" + response.getResult());
}

java复制代码@Test
public void doc_update() throws IOException {
    UpdateRequest request = new UpdateRequest();
    request.index("people").id("1001");

    request.doc(XContentType.JSON, "sex", "女");

    UpdateResponse response = esClient.update(request, RequestOptions.DEFAULT);

    System.out.println(response);
}

java复制代码@Test
public void doc_get() throws IOException {

    GetRequest request = new GetRequest();
    request.index("people").id("1001");

    GetResponse response = esClient.get(request, RequestOptions.DEFAULT);

    System.out.println(response);
    System.out.println(response.getSource());
}

java复制代码@Test
public void doc_delete() throws IOException {
    DeleteRequest request = new DeleteRequest();
    request.index("people").id("1001");

    DeleteResponse response = esClient.delete(request, RequestOptions.DEFAULT);
    System.out.println(response);
}

java复制代码@Test
public void doc_insert_batch() throws IOException {
    BulkRequest request = new BulkRequest();
    request.add(new IndexRequest().index("people").id("1001").source(XContentType.JSON, "name", "张三", "sex", "男", "age", 10));
    request.add(new IndexRequest().index("people").id("1002").source(XContentType.JSON, "name", "李四", "sex", "男", "age", 11));
    request.add(new IndexRequest().index("people").id("1003").source(XContentType.JSON, "name", "王五", "sex", "男", "age", 12));
    request.add(new IndexRequest().index("people").id("1004").source(XContentType.JSON, "name", "王五1", "sex", "男", "age", 8));
    request.add(new IndexRequest().index("people").id("1005").source(XContentType.JSON, "name", "王五2", "sex", "男", "age", 9));
    request.add(new IndexRequest().index("people").id("1006").source(XContentType.JSON, "name", "王五33", "sex", "男", "age", 7));

    BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);

    System.out.println(response.getTook());
    System.out.println(Arrays.toString(response.getItems()));
}

java复制代码@Test
public void doc_delete_batch() throws IOException {
    BulkRequest request = new BulkRequest();
    request.add(new DeleteRequest().index("people").id("1001"));
    request.add(new DeleteRequest().index("people").id("1002"));
    request.add(new DeleteRequest().index("people").id("1003"));

    BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);

    System.out.println(response.getTook());
    System.out.println(response);
}

java复制代码@Test
public void match_all() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.matchAllQuery());

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_term() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.termQuery("age", 10));

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_page() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.matchAllQuery());

    // from指定的是页数开始的偏移量， （当前页数 - 1）* size
    builder.from(0);
    builder.size(3);

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_sort() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.matchAllQuery());

    builder.sort("age", SortOrder.DESC);
    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_filter() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.matchAllQuery());

    String[] excludes = {};
    String[] includes = {"name"};
    // 过滤字段，指定只包含某些字段，或者需要排除某些字段
    builder.fetchSource(includes, excludes);

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_bool_must() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();

    // 多条件查询，must -> 一定需要匹配到
    boolQueryBuilder.must(QueryBuilders.matchQuery("age", 10));
    boolQueryBuilder.must(QueryBuilders.matchQuery("sex", "女"));


    builder.query(boolQueryBuilder);

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_bool_should() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();

    // 多条件查询，should -> 如果当前这条数据满足两个should条件中的任意一个，则表示满足条件
    boolQueryBuilder.should(QueryBuilders.matchQuery("age", 10));
    boolQueryBuilder.should(QueryBuilders.matchQuery("sex", "女"));

    builder.query(boolQueryBuilder);

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_range() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    // 根据某个字段构建范围查询
    RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("age");

    // 指定范围查询的条件数据
    rangeQueryBuilder.gte(9);
    rangeQueryBuilder.lte(12);

    builder.query(rangeQueryBuilder);

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_fuzzy() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    // 模糊查询，指定字段名称进行模糊查询，后面的指定模糊匹配的字符个数
    builder.query(QueryBuilders.fuzzyQuery("name", "王五").fuzziness(Fuzziness.ONE));

    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

    SearchHits hits = response.getHits();
    System.out.println("took:" + response.getTook());
    System.out.println("timeout:" + response.isTimedOut());
    System.out.println("total:" + hits.getTotalHits());
    System.out.println("MaxScore:" + hits.getMaxScore());
    System.out.println("hits========>>");
    for (SearchHit hit : hits) {
        //输出每条查询的结果信息
        System.out.println(hit.getSourceAsString());
    }
    System.out.println("<<========");
}

java复制代码@Test
public void query_highlight() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();
    TermsQueryBuilder termsQueryBuilder = QueryBuilders.termsQuery("sex", "女");

    // 设置查询方式
    builder.query(termsQueryBuilder);

    // 构建高亮字段
    HighlightBuilder highlightBuilder = new HighlightBuilder();
    highlightBuilder.preTags("<font color='red'>"); // 设置标签前缀
    highlightBuilder.postTags("</font>"); // 设置标签后缀
    highlightBuilder.field("sex"); // 设置高亮字段

    // 设置高亮查询
    builder.highlighter(highlightBuilder);

    // 设置请求体
    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
    System.out.println(response);
    SearchHits hits = response.getHits();
    System.out.println("took::"+response.getTook());
    System.out.println("time_out::"+response.isTimedOut());
    System.out.println("total::"+hits.getTotalHits());
    System.out.println("max_score::"+hits.getMaxScore());
    System.out.println("hits::::>>");
    for (SearchHit hit : hits) {
        String sourceAsString = hit.getSourceAsString();
        System.out.println(sourceAsString);
        //打印高亮结果
        Map<String, HighlightField> highlightFields = hit.getHighlightFields();
        System.out.println(highlightFields);
    }
}

java复制代码@Test
public void query_aggs_max() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    // 聚合查询，获取最大的age字段的数
    builder.aggregation(AggregationBuilders.max("maxAge").field("age"));

    // 设置请求体
    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
    System.out.println(response);
}

java复制代码@Test
public void query_aggs_group() throws IOException {
    SearchRequest request = new SearchRequest();
    request.indices("people");

    SearchSourceBuilder builder = new SearchSourceBuilder();

    // 聚合查询，获取最大的age字段的数
    builder.aggregation(AggregationBuilders.terms("age_groupby").field("age"));

    // 设置请求体
    request.source(builder);

    SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
    System.out.printl	n(response);
}