【原】Jmeter源码学习

shell学习

# 特殊变量
$0 # 当前脚本的文件名
$n # 传递给脚本或函数的参数。n 是一个数字，表示第几个参数。例如，第一个参数是$1，第二个参数是$2。
$# # 传递给脚本或函数的参数个数。
$* # 传递给脚本或函数的所有参数。
$@ # 传递给脚本或函数的所有参数。被双引号(" ")包含时，与 $* 稍有不同，下面将会讲到。
$? # 上个命令的退出状态，或函数的返回值。
$$ # 当前Shell进程ID。对于 Shell 脚本，就是这些脚本所在的进程ID。

# 条件判断
[ -a FILE ] 如果 FILE 存在则为真。
[ -b FILE ] 如果 FILE 存在且是一个块特殊文件则为真。
[ -c FILE ] 如果 FILE 存在且是一个字特殊文件则为真。
[ -d FILE ] 如果 FILE 存在且是一个目录则为真。
[ -e FILE ] 如果 FILE 存在则为真。
[ -f FILE ] 如果 FILE 存在且是一个普通文件则为真。
[ -g FILE ] 如果 FILE 存在且已经设置了SGID则为真。
[ -h FILE ] 如果 FILE 存在且是一个符号连接则为真。
[ -k FILE ] 如果 FILE 存在且已经设置了粘制位则为真。
[ -p FILE ] 如果 FILE 存在且是一个名字管道(F如果O)则为真。
[ -r FILE ] 如果 FILE 存在且是可读的则为真。
[ -s FILE ] 如果 FILE 存在且大小不为0则为真。  
[ -t FD ] 如果文件描述符 FD 打开且指向一个终端则为真。
[ -u FILE ] 如果 FILE 存在且设置了SUID (set user ID)则为真。
[ -w FILE ] 如果 FILE 如果 FILE 存在且是可写的则为真。
[ -x FILE ] 如果 FILE 存在且是可执行的则为真。
[ -O FILE ] 如果 FILE 存在且属有效用户ID则为真。
[ -G FILE ] 如果 FILE 存在且属有效用户组则为真。
[ -L FILE ] 如果 FILE 存在且是一个符号连接则为真。  
[ -N FILE ] 如果 FILE 存在 and has been mod如果ied since it was last read则为真。
[ -S FILE ] 如果 FILE 存在且是一个套接字则为真。  
[ FILE1 -nt FILE2 ] 如果 FILE1 has been changed more recently than FILE2,or 如果 FILE1 exists and FILE2 does not则为真。  
[ FILE1 -ot FILE2 ] 如果 FILE1 比 FILE2 要老, 或者 FILE2 存在且 FILE1 不存在则为真。  
[ FILE1 -ef FILE2 ] 如果 FILE1 和 FILE2 指向相同的设备和节点号则为真。
[ -o OPTIONNAME ] 如果 shell选项 “OPTIONNAME” 开启则为真。
[ -z STRING ] “STRING” 的长度为零则为真。  
[ -n STRING ] or [ STRING ] “STRING” 的长度为非零 non-zero则为真。
[ ARG1 OP ARG2 ] “OP” is one of -eq, -ne, -lt, -le, -gt or -ge. These arithmetic binary operators return true if “ARG1” is equal to, not equal to, less than, less than or equal to, greater than, or greater than or equal to “ARG2”, respectively. “ARG1” and “ARG2” are integers. 

# 数字判断
[ $count -gt "1"] 如果$count 大于1 为真
-gt  大于
-lt    小于
-ne  不等于
-eq  等于
-ge  大于等于
-le  小于等于

# 字符串
[ STRING1 == STRING2 ] 如果2个字符串相同。 “=” may be used instead of “==” for strict POSIX compliance则为真。  
[ STRING1 != STRING2 ] 如果字符串不相等则为真。  
[ STRING1 < STRING2 ] 如果 “STRING1” sorts before “STRING2” lexicographically in the current locale则为真。  
[ STRING1 > STRING2 ] 如果 “STRING1” sorts after “STRING2” lexicographically in the current locale则为真。 

jmeter.sh学习

#! /bin/sh

##   Licensed to the Apache Software Foundation (ASF) under one or more
##   contributor license agreements.  See the NOTICE file distributed with
##   this work for additional information regarding copyright ownership.
##   The ASF licenses this file to You under the Apache License, Version 2.0
##   (the "License"); you may not use this file except in compliance with
##   the License.  You may obtain a copy of the License at
## 
##       http://www.apache.org/licenses/LICENSE-2.0
## 
##   Unless required by applicable law or agreed to in writing, software
##   distributed under the License is distributed on an "AS IS" BASIS,
##   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
##   See the License for the specific language governing permissions and
##   limitations under the License.

## This is a simple wrapper for the script bin/jmeter.sh
##
## Basic JMeter startup script for Un*x systems
## See the "jmeter" script for details of options that can be used for Sun JVMs

##   ==============================================
##   Environment variables:
##   JVM_ARGS - optional java args, e.g. -Dprop=val
##
##   e.g.
##   JVM_ARGS="-Xms512m -Xmx512m" jmeter.sh etc.
##
##   ==============================================

# resolve links - $0 may be a softlink (code as used by Tomcat)
# N.B. readlink would be a lot simpler but is not supported on Solaris
# 获取当前脚本名
PRG="$0"

# 判断当前脚本是否哦存在（肯定存在的），是否是一个符号连接
# 使PRG执向真实的文件，而不是连接
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

# 获取这个文件的路径
PRGDIR=`dirname "$PRG"`

# Make sure prerequisite environment variables are set
# 获取Java的环境变量信息
if [ -z "$JAVA_HOME" -a -z "$JRE_HOME" ]; then
  if [ "`uname`" = "Darwin" ]; then
    #
    if [ -x '/usr/libexec/java_home' ] ; then
      export JAVA_HOME=`/usr/libexec/java_home`
    #
    elif [ -d "/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home" ]; then
      export JAVA_HOME="/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home"
    fi
  else
    JAVA_PATH=`which java 2>/dev/null`
    if [ "x$JAVA_PATH" != "x" ]; then
      JAVA_PATH=`dirname $JAVA_PATH 2>/dev/null`
      JRE_HOME=`dirname $JAVA_PATH 2>/dev/null`
    fi
    if [ "x$JRE_HOME" = "x" ]; then
      # XXX: Should we try other locations?
      if [ -x /usr/bin/java ]; then
        JRE_HOME=/usr
      fi
    fi
  fi
  if [ -z "$JAVA_HOME" -a -z "$JRE_HOME" ]; then
    echo "Neither the JAVA_HOME nor the JRE_HOME environment variable is defined"
    echo "At least one of these environment variable is needed to run this program"
    exit 1
  fi
fi
if [ -z "$JAVA_HOME" -a "$1" = "debug" ]; then
  echo "JAVA_HOME should point to a JDK in order to run in debug mode."
  exit 1
fi
if [ -z "$JRE_HOME" ]; then
  JRE_HOME="$JAVA_HOME"
fi
if [ -z "$JAVA_HOME" ]; then
  JAVA_HOME="$JRE_HOME"
fi

#--add-opens if JAVA 9
JAVA9_OPTS=

# Minimal version to run JMeter
MINIMAL_VERSION=8

# Check if version is from OpenJDK or Oracle Hotspot JVM prior to 9 containing 1.${version}.x
CURRENT_VERSION=`"${JAVA_HOME}/bin/java" -version 2>&1 | awk -F'"' '/version/ {gsub("^1[.]", "", $2); gsub("[^0-9].*$", "", $2); print $2}'`

# Check if Java is present and the minimal version requirement
if [ "$CURRENT_VERSION" -gt "$MINIMAL_VERSION" ]; then
    JAVA9_OPTS="--add-opens java.desktop/sun.awt=ALL-UNNAMED --add-opens java.desktop/javax.swing.text.html=ALL-UNNAMED --add-opens java.desktop/sun.swing=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED"
fi

# Don't add additional arguments to the JVM start, except those needed for Java 9
# 除了Java 9所需的参数外，不要向JVM start添加其他参数
JMETER_COMPLETE_ARGS=true

# add the Java9 args before the user given ones
# 添加Java 9参数
JVM_ARGS="$JAVA9_OPTS $JVM_ARGS"
export JVM_ARGS JMETER_COMPLETE_ARGS

"${PRGDIR}/jmeter" "$@"

jmeter学习（入口脚本文件）

#! /bin/sh

##   Licensed to the Apache Software Foundation (ASF) under one or more
##   contributor license agreements.  See the NOTICE file distributed with
##   this work for additional information regarding copyright ownership.
##   The ASF licenses this file to You under the Apache License, Version 2.0
##   (the "License"); you may not use this file except in compliance with
##   the License.  You may obtain a copy of the License at
##
##       http://www.apache.org/licenses/LICENSE-2.0
##
##   Unless required by applicable law or agreed to in writing, software
##   distributed under the License is distributed on an "AS IS" BASIS,
##   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
##   See the License for the specific language governing permissions and
##   limitations under the License.

##   ==============================================
##   Environment variables:
##   JVM_ARGS - optional java args, e.g. -Dprop=val
##
##   e.g.
##   JVM_ARGS="-Xms1g -Xmx1g" jmeter etc.
##
##   Do not set the variables in this script. Instead put them into a script
##   setenv.sh in JMETER_HOME/bin to keep your customizations separate.
##
##   JAVA_HOME        Must point at your Java Development Kit installation.
##                    Required to run the with the "debug" argument.
##
##   JRE_HOME         Must point at your Java Runtime installation.
##                    Defaults to JAVA_HOME if empty. If JRE_HOME and JAVA_HOME
##                    are both empty, JMeter will try to guess JAVA_HOME.
##                    If JRE_HOME and JAVA_HOME are both set, JAVA_HOME is used.
##
##   GC_ALGO          (Optional) Java runtime options to specify JVM garbage collection
##                    algorithm
##                    Defaults to "-XX:+UseG1GC -XX:MaxGCPauseMillis=100 -XX:G1ReservePercent=20"
##
##   HEAP             (Optional) Java runtime options for memory management
##                    used when JMeter is started.
##                    Defaults to "-Xms1g -Xmx1g -XX:MaxMetaspaceSize=256m"
##
##   JMETER_HOME      (Optional) May point to your JMeter install dir. If empty
##                    it will be set relativ to this script.
##
##   JMETER_LANGUAGE  (Optional) Java runtime options to specify used language
##                    Defaults to "-Duser.language=en -Duser.region=EN"
##
##   JMETER_OPTS      (Optional) Java runtime options used when JMeter is started.
##                    Special options for operating systems might be added by JMeter.
##
##   ==============================================

# resolve links - $0 may be a softlink (code as used by Tomcat)
# N.B. readlink would be a lot simpler but is not supported on Solaris
PRG="$0"

# 获取脚本真实路径，防止是一个软连接
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

# 获取当前路径，上一级就是Jmeter的根目录
PRGDIR=`dirname "$PRG"`

# Only set JMETER_HOME if not already set
[ -z "$JMETER_HOME" ] && JMETER_HOME=`cd "$PRGDIR/.." >/dev/null; pwd`

# 执行环境设置脚本，设置的环境信息有：
if [ -r "${JMETER_HOME}/bin/setenv.sh" ]; then
  . "${JMETER_HOME}/bin/setenv.sh"
fi

# Make sure prerequisite environment variables are set
# 确保Java环境是OK的
if [ -z "$JAVA_HOME" -a -z "$JRE_HOME" ]; then
  if [ "`uname`" = "Darwin" ]; then
    #
    if [ -x '/usr/libexec/java_home' ] ; then
      export JAVA_HOME=`/usr/libexec/java_home`
    #
    elif [ -d "/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home" ]; then
      export JAVA_HOME="/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home"
    fi
  else
    JAVA_PATH=`which java 2>/dev/null`
    if [ "x$JAVA_PATH" != "x" ]; then
      JAVA_PATH=`dirname $JAVA_PATH 2>/dev/null`
      JRE_HOME=`dirname $JAVA_PATH 2>/dev/null`
    fi
    if [ "x$JRE_HOME" = "x" ]; then
      # XXX: Should we try other locations?
      if [ -x /usr/bin/java ]; then
        JRE_HOME=/usr
      fi
    fi
  fi
  if [ -z "$JAVA_HOME" -a -z "$JRE_HOME" ]; then
    echo "Neither the JAVA_HOME nor the JRE_HOME environment variable is defined"
    echo "At least one of these environment variable is needed to run this program"
    exit 1
  fi
fi
if [ -z "$JAVA_HOME" -a "$1" = "debug" ]; then
  echo "JAVA_HOME should point to a JDK in order to run in debug mode."
  exit 1
fi
if [ -z "$JRE_HOME" ]; then
  JRE_HOME="$JAVA_HOME"
fi
if [ -z "$JAVA_HOME" ]; then
  JAVA_HOME="$JRE_HOME"
fi

#--add-opens if JAVA 9
JAVA9_OPTS=

# Minimal version to run JMeter
MINIMAL_VERSION=8

# Check if version is from OpenJDK or Oracle Hotspot JVM prior to 9 containing 1.${version}.x
CURRENT_VERSION=`"${JAVA_HOME}/bin/java" -version 2>&1 | awk -F'"' '/version/ {gsub("^1[.]", "", $2); gsub("[^0-9].*$", "", $2); print $2}'`

# Check if Java is present and the minimal version requirement
if [ "$CURRENT_VERSION" -gt "$MINIMAL_VERSION" ]; then
    JAVA9_OPTS="--add-opens java.desktop/sun.awt=ALL-UNNAMED --add-opens java.desktop/sun.swing=ALL-UNNAMED --add-opens java.desktop/javax.swing.text.html=ALL-UNNAMED --add-opens java.desktop/java.awt=ALL-UNNAMED --add-opens java.desktop/java.awt.font=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.base/java.lang.reflect=ALL-UNNAMED --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.text=ALL-UNNAMED --add-opens=java.desktop/sun.awt.X11=ALL-UNNAMED"
fi

: "${JMETER_OPTS:=""}"
case `uname` in
   Darwin*)
   # Add Mac-specific property - should be ignored elsewhere (Bug 47064)
   JMETER_OPTS="${JMETER_OPTS} -Xdock:name=JMeter -Xdock:icon=\"${PRGDIR}/../docs/images/jmeter_square.png\" -Dapple.laf.useScreenMenuBar=true -Dapple.eawt.quitStrategy=CLOSE_ALL_WINDOWS"
   ;;
esac


#
# Original page has disappeared, it is now only available at:
# https://web.archive.org/web/20060614151434/http://www.atg.com/portal/myatg/developer?paf_dm=full&paf_gear_id=1100010&detailArticle=true&id=9606
#
# JMeter objects can generally be grouped into three life-length groups:
#
# - Per-sample objects (results, DOMs,...). An awful lot of those.
#   Life length of milliseconds to a few seconds.
#
# - Per-run objects (threads, listener data structures,...). Not that many
#   of those unless we use the table or tree listeners on heavy runs.
#   Life length of minutes to several hours, from creation to start of next run.
#
# - Per-work-session objects (test plans, GUIs,...).
#   Life length: for the life of the JVM.

# This is the base heap size -- you may increase or decrease it to fit your
# system's memory availability:
: "${HEAP:="-Xms1g -Xmx1g -XX:MaxMetaspaceSize=256m"}"

# Set language
# Default to en_EN
: "${JMETER_LANGUAGE:="-Duser.language=en -Duser.region=EN"}"

# Uncomment this to generate GC verbose file with Java prior to 9
# VERBOSE_GC="-verbose:gc -Xloggc:gc_jmeter_%p.log -XX:+PrintGCDetails -XX:+PrintGCCause -XX:+PrintTenuringDistribution -XX:+PrintHeapAtGC -XX:+PrintGCApplicationConcurrentTime -XX:+PrintAdaptiveSizePolicy -XX:+PrintGCApplicationStoppedTime -XX:+PrintGCDateStamps"

# Uncomment this to generate GC verbose file with Java 9 and above
# VERBOSE_GC="-Xlog:gc*,gc+age=trace,gc+heap=debug:file=gc_jmeter_%p.log"

# Uncomment this if you run JMeter in DOCKER (need Java SE 8u131 or JDK 9)
# see https://blogs.oracle.com/java-platform-group/java-se-support-for-docker-cpu-and-memory-limits
# RUN_IN_DOCKER="-XX:+UnlockExperimentalVMOptions -XX:+UseCGroupMemoryLimitForHeap"

# Finally, some tracing to help in case things go astray:
# You may want to add those settings:
# -XX:+ParallelRefProcEnabled -XX:+PerfDisableSharedMem
: "${GC_ALGO:="-XX:+UseG1GC -XX:MaxGCPauseMillis=100 -XX:G1ReservePercent=20"}"


# Always dump on OOM (does not cost anything unless triggered)
DUMP="-XX:+HeapDumpOnOutOfMemoryError"
SYSTEM_PROPS="-Djava.security.egd=file:/dev/urandom"
SERVER="-server"

if [ -z "${JMETER_COMPLETE_ARGS}" ]; then
    ARGS="$JAVA9_OPTS $SERVER $DUMP $HEAP $VERBOSE_GC $GC_ALGO $SYSTEM_PROPS $JMETER_LANGUAGE $RUN_IN_DOCKER"
else
    ARGS=""
fi

"$JAVA_HOME/bin/java" $ARGS $JVM_ARGS $JMETER_OPTS -jar "$PRGDIR/ApacheJMeter.jar" "$@"