落地实践之JAVA应用启动脚本

前期大家分库分表相关的springboot工程，并通过打包脚本打成zip包的形式。如果放在linux环境上运行，还需要相关的启动脚本 前文文档如下：

1.MYSQL系列-分库分表（三）：Sharding-JDBC实现分库分表落地实践-上

2.落地实践之基于MAVEN的BUILD插件打包应用程序

整体思路

基于shell脚本开发3个脚本，分别是

• jvm启动参数相关的setjvment.sh，主要是jvm启动相关参数配置
• start.sh，主要是利用java命令启动进程，包含classpath和执行结果日志保存相关设置
• stop.sh,主要是停止java进程，包括优雅停止和强制停止

如果linux没有安装jdk，可使用如下命令安装jdk：

sudo apt update
sudo apt install openjdk-8-jdk

然后在启动的文件.bash_profile中设置环境变量JAVA_HOME,

#!/bin/sh
export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64

相关脚本

setjvm

#!/bin/bash

# 设置Java堆栈大小
JAVA_OPTS="$JAVA_OPTS -Xmn512m -Xms512m -Xmx1024m -XX:MetaspaceSize=64m -XX:MaxMetaspaceSize=256m"
JAVA_OPTS="$JAVA_OPTS -XX:SurvivorRatio=8 -XX:MaxTenuringThreshold=8 -XX:-UseAdaptiveSizePolicy"
# 垃圾收集器设置
JAVA_OPTS="$JAVA_OPTS -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+CMSParallelRemarkEnabled -XX:CMSInitiatingOccupancyFraction=60"
JAVA_OPTS="$JAVA_OPTS -XX:+CMSClassUnloadingEnabled"
# 打印GC日志
JAVA_OPTS="$JAVA_OPTS -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -XX:+PrintGCApplicationStoppedTime -XX:+UseGCLogFileRotation"
JAVA_OPTS="$JAVA_OPTS -XX:+PrintHeapAtGC -Xloggc:$work_home/logs/gc.log -XX:GCLogFileSize=1m -XX:NumberOfGCLogFiles=10"
# 打印DUMP日志
JAVA_OPTS="$JAVA_OPTS -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=$work_home/logs"
# 其他设置
JAVA_OPTS="$JAVA_OPTS -XX:+DisableExplicitGC  -XX:+UseFastAccessorMethods -XX:-UseBiasedLocking"
# 指定随机数生成器的种子源
JAVA_OPTS="$JAVA_OPTS -Djava.security.egd=file:/dev/urandom"
# 设置java.ext.dirs
JAVA_OPTS="$JAVA_OPTS -Djava.ext.dirs=$JAVA_HOME/jre/lib/ext:$work_home/lib"
# 其他环境变量或配置设置
# export OTHER_ENV_VARIABLE=example_value

start

#!/bin/bash

CUR="$0"

while [ -h "$CUR" ]; do
  ls=$(ls -ld "$CUR")
  link=$(expr "$ls" : '.-> (.)$')
  if expr "$link" : '/.*' >/dev/null; then
    CUR="$link"
  else
    CUR=$(dirname "$CUR")/"$link"
  fi
done

CUR_DIR=$(dirname "$CUR")

work_home=$(
  cd "$CUR_DIR/.." >/dev/null
  pwd
)

if [ -z $JAVA_HOME ]; then
  echo "plz set JAVA_HOME env."
  exit 1
fi

if [ -r "$work_home/bin/setenv.sh" ]; then
  . "$work_home/bin/setjvmenv.sh"
fi

CLASSPATH=$CLASSPATH:$work_home/lib/conf
LOG_DIR="$work_home/logs"

if [ ! -d $LOG_DIR ]; then
  mkdir "$LOG_DIR"
fi

main_class="com.toby.dynamic.data.source.start.PointApplication"
count=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|wc -l`
if [ $count != 0 ]; then
  app_id=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|awk '{print $2}'`
  echo "already running with pid $app_id, start aborted."
else
  echo "use java_home $JAVA_HOME"
  echo "use work_home $work_home"

  exec $JAVA_HOME/bin/java $JAVA_OPTS -cp $CLASSPATH \
  -Dwork.home=$work_home -Djava.io.tmpdir=$work_home \
  $main_class >$LOG_DIR/server.log 2>&1 &

  echo "server started."
fi

stop

#!/bin/bash

PRG="$0"
while [ -h "$PRG" ]; do
  ls=$(ls -ld "$PRG")
  link=$(expr "$ls" : '.-> (.)$')
  if expr "$link" : '/.*' >/dev/null; then
    PRG="$link"
  else
    PRG=$(dirname "$PRG")/"$link"
  fi
done

PRGDIR=$(dirname "$PRG")

work_home=$(
  cd "$PRGDIR/.." >/dev/null
  pwd
)

main_class="com.toby.dynamic.data.source.start.PointApplication"
count=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|wc -l`
echo " stop server start."
if [ $count == 0 ]; then
  echo "already stop,return."
  exit 0
fi

app_id=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|awk '{print $2}'`
# 请求优雅退出
kill -15 $app_id
SLEEP=5
STOPPED=0

while [ $SLEEP -ge 0 ]; do
  count=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|wc -l`
  if [ $count == 0 ]; then
    STOPPED=1
    echo " server stopped."
    break;
  fi

  if [ $SLEEP -gt 0 ]; then
    sleep 1
  fi

  if [ $SLEEP -eq 0 ]; then
    echo "server did not stopped in time."
  fi
  SLEEP=`expr $SLEEP - 1 `
done

if [ $STOPPED -eq 0 ]; then
  echo "server killed fore"
  SLEEP=5
  kill -15 $app_id
  while [ $SLEEP -ge 0 ]; do
    count=`ps -ef|grep java|grep $work_home|grep $main_class|grep -v grep|wc -l`
    if [ $count == 0 ]; then
      STOPPED=1
      echo " server has been killed."
      break;
    fi

    if [ $SLEEP -gt 0 ]; then
      sleep 1
    fi

    if [ $SLEEP -eq 0 ]; then
      echo "server did not stopped in time."
    fi
    SLEEP=`expr $SLEEP - 1 `
  done
  if [ $STOPPED -eq 0 ]; then
    echo "server has not been killed completely yet."
  fi
fi

执行结果