content: package com.taobao.arthas.core.command.monitor200;
  
  import com.alibaba.arthas.deps.org.slf4j.Logger;
  import com.alibaba.arthas.deps.org.slf4j.LoggerFactory;
  import com.taobao.arthas.core.advisor.AccessPoint;
  import com.taobao.arthas.core.advisor.Advice;
  import com.taobao.arthas.core.advisor.AdviceListenerAdapter;
  import com.taobao.arthas.core.advisor.ArthasMethod;
  import com.taobao.arthas.core.command.model.ObjectVO;
  import com.taobao.arthas.core.command.model.WatchModel;
  import com.taobao.arthas.core.shell.command.CommandProcess;
  import com.taobao.arthas.core.util.LogUtil;
  import com.taobao.arthas.core.util.ThreadLocalWatch;
  
  import java.time.LocalDateTime;
  
  /**
   * @author beiwei30 on 29/11/2016.
   */
  class WatchAdviceListener extends AdviceListenerAdapter {
  
      private static final Logger logger = LoggerFactory.getLogger(WatchAdviceListener.class);
      private final ThreadLocalWatch threadLocalWatch = new ThreadLocalWatch();
      private WatchCommand command;
      private CommandProcess process;
  
      public WatchAdviceListener(WatchCommand command, CommandProcess process, boolean verbose) {
          this.command = command;
          this.process = process;
          super.setVerbose(verbose);
      }
  
      private boolean isFinish() {
          return command.isFinish() || !command.isBefore() && !command.isException() && !command.isSuccess();
      }
  
      @Override
      public void before(ClassLoader loader, Class<?> clazz, ArthasMethod method, Object target, Object[] args)
              throws Throwable {
          // 开始计算本次方法调用耗时
          threadLocalWatch.start();
          if (command.isBefore()) {
              watching(Advice.newForBefore(loader, clazz, method, target, args));
          }
      }
  
      @Override
      public void afterReturning(ClassLoader loader, Class<?> clazz, ArthasMethod method, Object target, Object[] args,
                                 Object returnObject) throws Throwable {
          Advice advice = Advice.newForAfterReturning(loader, clazz, method, target, args, returnObject);
          if (command.isSuccess()) {
              watching(advice);
          }
  
          finishing(advice);
      }
  
      @Override
      public void afterThrowing(ClassLoader loader, Class<?> clazz, ArthasMethod method, Object target, Object[] args,
                                Throwable throwable) {
          Advice advice = Advice.newForAfterThrowing(loader, clazz, method, target, args, throwable);
          if (command.isException()) {
              watching(advice);
          }
  
          finishing(advice);
      }
  
      private void finishing(Advice advice) {
          if (isFinish()) {
              watching(advice);
          }
      }
  
  
      private void watching(Advice advice) {
          try {
              // 本次调用的耗时
              double cost = threadLocalWatch.costInMillis();
              boolean conditionResult = isConditionMet(command.getConditionExpress(), advice, cost);
              if (this.isVerbose()) {
                  process.write("Condition express: " + command.getConditionExpress() + " , result: " + conditionResult + "\n");
              }
              if (conditionResult) {
                  // TODO: concurrency issues for process.write
  
                  Object value = getExpressionResult(command.getExpress(), advice, cost);
  
                  WatchModel model = new WatchModel();
                  model.setTs(LocalDateTime.now());
                  model.setCost(cost);
                  model.setValue(new ObjectVO(value, command.getExpand()));
                  model.setSizeLimit(command.getSizeLimit());
                  model.setClassName(advice.getClazz().getName());
                  model.setMethodName(advice.getMethod().getName());
                  if (advice.isBefore()) {
                      model.setAccessPoint(AccessPoint.ACCESS_BEFORE.getKey());
                  } else if (advice.isAfterReturning()) {
                      model.setAccessPoint(AccessPoint.ACCESS_AFTER_RETUNING.getKey());
                  } else if (advice.isAfterThrowing()) {
                      model.setAccessPoint(AccessPoint.ACCESS_AFTER_THROWING.getKey());
                  }
  
                  process.appendResult(model);
                  process.times().incrementAndGet();
                  if (isLimitExceeded(command.getNumberOfLimit(), process.times().get())) {
                      abortProcess(process, command.getNumberOfLimit());
                  }
              }
          } catch (Throwable e) {
              logger.warn("watch failed.", e);
              process.end(-1, "watch failed, condition is: " + command.getConditionExpress() + ", express is: "
                      + command.getExpress() + ", " + e.getMessage() + ", visit " + LogUtil.loggingFile()
                      + " for more details.");
          }
      }
  }
  