hive源码阅读--CliDriver

说明：根据自己捣鼓的做下记录，草稿，以后再修改

hive-1.2.1版本

根据查询调试阅读

在hive-cli的debug模式下输入use test;

 private int executeDriver(CliSessionState ss, HiveConf conf, OptionsProcessor oproc)
      throws Exception {

    CliDriver cli = new CliDriver();
    cli.setHiveVariables(oproc.getHiveVariables());

    // use the specified database if specified
    cli.processSelectDatabase(ss);

    // Execute -i init files (always in silent mode)
    cli.processInitFiles(ss);

    if (ss.execString != null) {
      int cmdProcessStatus = cli.processLine(ss.execString);
      return cmdProcessStatus;
    }

    try {
      if (ss.fileName != null) {
        return cli.processFile(ss.fileName);
      }
    } catch (FileNotFoundException e) {
      System.err.println("Could not open input file for reading. (" + e.getMessage() + ")");
      return 3;
    }

    setupConsoleReader();

    String line;
    int ret = 0;
    String prefix = "";
    String curDB = getFormattedDb(conf, ss);
    String curPrompt = prompt + curDB;
    String dbSpaces = spacesForString(curDB);

    while ((line = reader.readLine(curPrompt + "> ")) != null) {    //从此处开始往下执行
      if (!prefix.equals("")) {
        prefix += '\n';
      }
      if (line.trim().endsWith(";") && !line.trim().endsWith("\\;")) {
        line = prefix + line;
        ret = cli.processLine(line, true);
        prefix = "";
        curDB = getFormattedDb(conf, ss);
        curPrompt = prompt + curDB;
        dbSpaces = dbSpaces.length() == curDB.length() ? dbSpaces : spacesForString(curDB);
      } else {
        prefix = prefix + line;
        curPrompt = prompt2 + dbSpaces;
        continue;
      }
    }

    return ret;
  }

line ="use test;"

prefix=""

ret = cli.processLine(line, true);
 

  public int processLine(String line, boolean allowInterrupting) {
    SignalHandler oldSignal = null;
    Signal interruptSignal = null;

    if (allowInterrupting) {
      // Remember all threads that were running at the time we started line processing.
      // Hook up the custom Ctrl+C handler while processing this line
      interruptSignal = new Signal("INT");
      oldSignal = Signal.handle(interruptSignal, new SignalHandler() {
        private final Thread cliThread = Thread.currentThread();
        private boolean interruptRequested;

        @Override
        public void handle(Signal signal) {
          boolean initialRequest = !interruptRequested;
          interruptRequested = true;

          // Kill the VM on second ctrl+c
          if (!initialRequest) {
            console.printInfo("Exiting the JVM");
            System.exit(127);
          }

          // Interrupt the CLI thread to stop the current statement and return
          // to prompt
          console.printInfo("Interrupting... Be patient, this might take some time.");
          console.printInfo("Press Ctrl+C again to kill JVM");

          // First, kill any running MR jobs
          HadoopJobExecHelper.killRunningJobs();
          TezJobExecHelper.killRunningJobs();
          HiveInterruptUtils.interrupt();
        }
      });
    }

    try {
      int lastRet = 0, ret = 0;

      String command = "";
      for (String oneCmd : line.split(";")) {

        if (StringUtils.endsWith(oneCmd, "\\")) {
          command += StringUtils.chop(oneCmd) + ";";
          continue;
        } else {
          command += oneCmd;
        }
        if (StringUtils.isBlank(command)) {
          continue;
        }

        ret = processCmd(command);  //调用processCmd
        //wipe cli query state
        SessionState ss = SessionState.get();
        ss.setCommandType(null);
        command = "";
        lastRet = ret;
        boolean ignoreErrors = HiveConf.getBoolVar(conf, HiveConf.ConfVars.CLIIGNOREERRORS);
        if (ret != 0 && !ignoreErrors) {
          CommandProcessorFactory.clean((HiveConf) conf);
          return ret;
        }
      }
      CommandProcessorFactory.clean((HiveConf) conf);
      return lastRet;
    } finally {
      // Once we are done processing the line, restore the old handler
      if (oldSignal != null && interruptSignal != null) {
        Signal.handle(interruptSignal, oldSignal);
      }
    }
  }

然后：

 public int processCmd(String cmd) {
    CliSessionState ss = (CliSessionState) SessionState.get();
    ss.setLastCommand(cmd);
    // Flush the print stream, so it doesn't include output from the last command
    ss.err.flush();
    String cmd_trimmed = cmd.trim();
    String[] tokens = tokenizeCmd(cmd_trimmed);
    int ret = 0;

    if (cmd_trimmed.toLowerCase().equals("quit") || cmd_trimmed.toLowerCase().equals("exit")) {

      // if we have come this far - either the previous commands
      // are all successful or this is command line. in either case
      // this counts as a successful run
      ss.close();
      System.exit(0);

    } else if (tokens[0].equalsIgnoreCase("source")) {
      String cmd_1 = getFirstCmd(cmd_trimmed, tokens[0].length());
      cmd_1 = new VariableSubstitution().substitute(ss.getConf(), cmd_1);

      File sourceFile = new File(cmd_1);
      if (! sourceFile.isFile()){
        console.printError("File: "+ cmd_1 + " is not a file.");
        ret = 1;
      } else {
        try {
          ret = processFile(cmd_1);
        } catch (IOException e) {
          console.printError("Failed processing file "+ cmd_1 +" "+ e.getLocalizedMessage(),
            stringifyException(e));
          ret = 1;
        }
      }
    } else if (cmd_trimmed.startsWith("!")) {

      String shell_cmd = cmd_trimmed.substring(1);
      shell_cmd = new VariableSubstitution().substitute(ss.getConf(), shell_cmd);

      // shell_cmd = "/bin/bash -c \'" + shell_cmd + "\'";
      try {
        ShellCmdExecutor executor = new ShellCmdExecutor(shell_cmd, ss.out, ss.err);
        ret = executor.execute();
        if (ret != 0) {
          console.printError("Command failed with exit code = " + ret);
        }
      } catch (Exception e) {
        console.printError("Exception raised from Shell command " + e.getLocalizedMessage(),
            stringifyException(e));
        ret = 1;
      }
    }  else { // local mode
      try {
        CommandProcessor proc = CommandProcessorFactory.get(tokens, (HiveConf) conf);
        ret = processLocalCmd(cmd, proc, ss);
      } catch (SQLException e) {
        console.printError("Failed processing command " + tokens[0] + " " + e.getLocalizedMessage(),
          org.apache.hadoop.util.StringUtils.stringifyException(e));
        ret = 1;
      }
    }

    return ret;
  }

执行：

      try {
        CommandProcessor proc = CommandProcessorFactory.get(tokens, (HiveConf) conf);
        ret = processLocalCmd(cmd, proc, ss);
      } catch (SQLException e) {
        console.printError("Failed processing command " + tokens[0] + " " + e.getLocalizedMessage(),
          org.apache.hadoop.util.StringUtils.stringifyException(e));
        ret = 1;
      }

  int processLocalCmd(String cmd, CommandProcessor proc, CliSessionState ss) {
    int tryCount = 0;
    boolean needRetry;
    int ret = 0;

    do {
      try {
        needRetry = false;
        if (proc != null) {
          if (proc instanceof Driver) {
            Driver qp = (Driver) proc;
            PrintStream out = ss.out;
            long start = System.currentTimeMillis();
            if (ss.getIsVerbose()) {
              out.println(cmd);
            }

            qp.setTryCount(tryCount);
            ret = qp.run(cmd).getResponseCode();
            if (ret != 0) {
              qp.close();
              return ret;
            }

            // query has run capture the time
            long end = System.currentTimeMillis();
            double timeTaken = (end - start) / 1000.0;

            ArrayList res = new ArrayList();

            printHeader(qp, out);

            // print the results
            int counter = 0;
            try {
              if (out instanceof FetchConverter) {
                ((FetchConverter)out).fetchStarted();
              }
              while (qp.getResults(res)) {
                for (String r : res) {
                  out.println(r);
                }
                counter += res.size();
                res.clear();
                if (out.checkError()) {
                  break;
                }
              }
            } catch (IOException e) {
              console.printError("Failed with exception " + e.getClass().getName() + ":"
                  + e.getMessage(), "\n"
                  + org.apache.hadoop.util.StringUtils.stringifyException(e));
              ret = 1;
            }

            int cret = qp.close();
            if (ret == 0) {
              ret = cret;
            }

            if (out instanceof FetchConverter) {
              ((FetchConverter)out).fetchFinished();
            }

            console.printInfo("Time taken: " + timeTaken + " seconds" +
                (counter == 0 ? "" : ", Fetched: " + counter + " row(s)"));
          } else {
            String firstToken = tokenizeCmd(cmd.trim())[0];
            String cmd_1 = getFirstCmd(cmd.trim(), firstToken.length());

            if (ss.getIsVerbose()) {
              ss.out.println(firstToken + " " + cmd_1);
            }
            CommandProcessorResponse res = proc.run(cmd_1);
            if (res.getResponseCode() != 0) {
              ss.out.println("Query returned non-zero code: " + res.getResponseCode() +
                  ", cause: " + res.getErrorMessage());
            }
            ret = res.getResponseCode();
          }
        }
      } catch (CommandNeedRetryException e) {
        console.printInfo("Retry query with a different approach...");
        tryCount++;
        needRetry = true;
      }
    } while (needRetry);

    return ret;
  }

ret = 0

 

 

Signal.handle(interruptSignal, oldSignal);  ===> return lastRet; ===> ret = cli.processLine(line, true); (736行)