检查最耗cpu的java线程，给出cpu的使用率和堆栈信息，只能用于linux系统

busythread.sh

#!/bin/bash

if [ $# -eq 0 ];then
  echo "please enter java pid"
  exit -1
fi

pid=$1
jstack_cmd=""

if [[ $JAVA_HOME != "" ]]; then
  jstack_cmd="$JAVA_HOME/bin/jstack"
else
  r=`which jstack 2>/dev/null`
  if [[ $r != "" ]]; then
    jstack_cmd=$r
  else
    echo "can not find jstack"
    exit -2
  fi
fi

line=`top -H  -o %CPU -b -n 1  -p $pid | sed '1,/^$/d' | grep -v $pid | awk 'NR==2'`
echo "$line" | awk '{print "tid: "$1," cpu: %"$9}'
tid_0x=`printf "%0x" $(echo "$line" | awk '{print $1}')`
$jstack_cmd $pid | grep $tid_0x -A20 | sed -n '1,/^$/p'