分析catalina.sh腳本的目的，一個(gè)是學(xué)習(xí)腳本中shell的各類用法，還有就是為編寫tomcat多服務(wù)器遠(yuǎn)程啟動(dòng)腳本做準(zhǔn)備，實(shí)現(xiàn)版本上線自動(dòng)化無(wú)人干預(yù)部署，此前作者已發(fā)表“ tomcat變量環(huán)境腳本setclasspath.sh分析”來(lái)為此篇作為鋪墊，需要兩篇文章一起看，才能全面的分析出tomcat的啟動(dòng)過程。
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tomcat版本：6.0.35
重慶分公司
重慶分公司
#!/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.
# -----------------------------------------------------------------------------
# Start/Stop Script for the CATALINA Server
#
# Environment Variable Prerequisites
#
# CATALINA_HOME May point at your Catalina "build" directory.
#
# CATALINA_BASE (Optional) Base directory for resolving dynamic portions
# of a Catalina installation. If not present, resolves to
# the same directory that CATALINA_HOME points to.
#
# CATALINA_OUT (Optional) Full path to a file where stdout and stderr
# will be redirected.
# Default is $CATALINA_BASE/logs/catalina.out
#
# CATALINA_OPTS (Optional) Java runtime options used when the "start",
# or "run" command is executed.
#
# CATALINA_TMPDIR (Optional) Directory path location of temporary directory
# the JVM should use (java.io.tmpdir). Defaults to
# $CATALINA_BASE/temp.
#
# 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 Development Kit installation.
# Defaults to JAVA_HOME if empty.
#
# JAVA_OPTS (Optional) Java runtime options used when the "start",
# "stop", or "run" command is executed.
#
# JAVA_ENDORSED_DIRS (Optional) Lists of of colon separated directories
# containing some jars in order to allow replacement of APIs
# created outside of the JCP (i.e. DOM and SAX from W3C).
# It can also be used to update the XML parser implementation.
# Defaults to $CATALINA_HOME/endorsed.
#
# JPDA_TRANSPORT (Optional) JPDA transport used when the "jpda start"
# command is executed. The default is "dt_socket".
#
# JPDA_ADDRESS (Optional) Java runtime options used when the "jpda start"
# command is executed. The default is 8000.
#
# JPDA_SUSPEND (Optional) Java runtime options used when the "jpda start"
# command is executed. Specifies whether JVM should suspend
# execution immediately after startup. Default is "n".
#
# JPDA_OPTS (Optional) Java runtime options used when the "jpda start"
# command is executed. If used, JPDA_TRANSPORT, JPDA_ADDRESS,
# and JPDA_SUSPEND are ignored. Thus, all required jpda
# options MUST be specified. The default is:
#
# -agentlib:jdwp=transport=$JPDA_TRANSPORT,
# address=$JPDA_ADDRESS,server=y,suspend=$JPDA_SUSPEND
#
# CATALINA_PID (Optional) Path of the file which should contains the pid
# of catalina startup java process, when start (fork) is used
#
# LOGGING_CONFIG (Optional) Override Tomcat's logging config file
# Example (all one line)
# LOGGING_CONFIG="-Djava.util.logging.config.file=$CATALINA_BASE/conf/logging.properties"
#
# LOGGING_MANAGER (Optional) Override Tomcat's logging manager
# Example (all one line)
# LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"
#
# $Id: catalina.sh 1146097 2011-07-13 15:25:05Z markt $
# -----------------------------------------------------------------------------
export JRE_HOME=/usr/java/jdk1.6.0_38
export CATALINA_HOME=/home/xrltest1/tomcat
JAVA_OPTS="-server -Xms2048m -Xmx2048m -Xmn768m -XX:PermSize=128m -XX:MaxPermSize=256m -XX:+UseParallelOldGC -XX:+PrintGCDateStamps -XX:+PrintGCDetails -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/home/xrltest1/tomcat/dumpfile/heap.bin -Xloggc:/home/xrltest1/tomcat/logs/gc.log"
#作者添加的環(huán)境申明，如果一臺(tái)服務(wù)器中有多臺(tái)tomcat要使用不同版本的JVM，就可以直接這這邊添加JRE_HOME，不需要再/etc/profile.d中再配置JRE_HOME環(huán)境變量
# OS specific support. $var _must_ be set to either true or false.
#此處語(yǔ)句判斷操作系統(tǒng)，同時(shí)對(duì)操作系統(tǒng)支持
#os400是 IBM的AIX
#darwin是MacOSX 操作環(huán)境的操作系統(tǒng)成份
#Darwin是windows平臺(tái)上運(yùn)行的類UNIX模擬環(huán)境
cygwin=false
os400=false
darwin=false
case "`uname`" in
CYGWIN*) cygwin=true;;
OS400*) os400=true;;
Darwin*) darwin=true;;
esac
# resolve links - $0 may be a softlink
#此處的RPG抓取的是文件名，因?yàn)榭赡苁欠?hào)鏈接，所以下面循環(huán)語(yǔ)句的作用就是找到文件真實(shí)源路徑
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"`/"$link"
fi
done
#獲取腳本目錄真實(shí)目錄地址
# Get standard environment variables
PRGDIR=`dirname "$PRG"`
# Only set CATALINA_HOME if not already set
[ -z "$CATALINA_HOME" ] && CATALINA_HOME=`cd "$PRGDIR/.." >/dev/null; pwd`
# Copy CATALINA_BASE from CATALINA_HOME if not already set
[ -z "$CATALINA_BASE" ] && CATALINA_BASE="$CATALINA_HOME"
#上面兩個(gè)語(yǔ)句判斷變量$CATALINA_HOME和$CATALINA_BASE是否存在，不存在則給予附值
#CATALINA_BASE="$CATALINA_HOME"
# Ensure that any user defined CLASSPATH variables are not used on startup,
# but allow them to be specified in setenv.sh, in rare case when it is needed.
CLASSPATH=
#test –r File 文件存在并且可讀
if [ -r "$CATALINA_BASE/bin/setenv.sh" ]; then
. "$CATALINA_BASE/bin/setenv.sh"
elif [ -r "$CATALINA_HOME/bin/setenv.sh" ]; then
. "$CATALINA_HOME/bin/setenv.sh"
fi
#默認(rèn)的tomcat的bin目錄下沒有這個(gè)文件，可以自行編寫setenv.sh這個(gè)文件設(shè)定環(huán)境變量
# For Cygwin, ensure paths are in UNIX format before anything is touched
if $cygwin; then
[ -n "$JAVA_HOME" ] && JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
[ -n "$JRE_HOME" ] && JRE_HOME=`cygpath --unix "$JRE_HOME"`
[ -n "$CATALINA_HOME" ] && CATALINA_HOME=`cygpath --unix "$CATALINA_HOME"`
[ -n "$CATALINA_BASE" ] && CATALINA_BASE=`cygpath --unix "$CATALINA_BASE"`
[ -n "$CLASSPATH" ] && CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
fi
# For OS400
if $os400; then
# Set job priority to standard for interactive (interactive - 6) by using
# the interactive priority - 6, the helper threads that respond to requests
# will be running at the same priority as interactive jobs.
COMMAND='chgjob job('$JOBNAME') runpty(6)'
system $COMMAND
# Enable multi threading
export QIBM_MULTI_THREADED=Y
fi
# Get standard Java environment variables
if $os400; then
# -r will Only work on the os400 if the files are:
# 1. owned by the user
# 2. owned by the PRIMARY group of the user
# this will not work if the user belongs in secondary groups
BASEDIR="$CATALINA_HOME"
. "$CATALINA_HOME"/bin/setclasspath.sh
else
#這點(diǎn)一定要注意了，本腳本中沒有賦值卻突然冒出的變量
#都是在setclasspath.sh這個(gè)腳本中執(zhí)行賦值的。比如$_RUNJAVA
#作者會(huì)在下一篇文章中，分析setclasspath.sh這個(gè)腳本
if [ -r "$CATALINA_HOME"/bin/setclasspath.sh ]; then
BASEDIR="$CATALINA_HOME"
. "$CATALINA_HOME"/bin/setclasspath.sh
else
echo "Cannot find $CATALINA_HOME/bin/setclasspath.sh"
echo "This file is needed to run this program"
exit 1
fi
fi
#以上是出現(xiàn)在其他操作環(huán)境下的腳本的可用性設(shè)置，因默認(rèn)linux系統(tǒng)，上面就不做解讀了
if [ -z "$CATALINA_BASE" ] ; then
CATALINA_BASE="$CATALINA_HOME"
fi
#將變量賦值
# Add tomcat-juli.jar and bootstrap.jar to classpath
# tomcat-juli.jar can be over-ridden per instance
if [ ! -z "$CLASSPATH" ] ; then
CLASSPATH="$CLASSPATH":
fi
#雖然前面已將做出CATALINA_BASE="$CATALINA_HOME"的語(yǔ)句
#此處還是添加了判斷，增強(qiáng)了代碼的健壯性
#添加變量$CLASSPATH的值
if [ "$CATALINA_BASE" != "$CATALINA_HOME" ] && [ -r "$CATALINA_BASE/bin/tomcat-juli.jar" ] ; then
CLASSPATH="$CLASSPATH""$CATALINA_BASE"/bin/tomcat-juli.jar:"$CATALINA_HOME"/bin/bootstrap.jar
else
CLASSPATH="$CLASSPATH""$CATALINA_HOME"/bin/bootstrap.jar
fi
#確認(rèn)日志路徑$CATALINA_OUT
#這部分主要判斷這些變量是否預(yù)定義，有就以預(yù)定義為主，沒有就設(shè)置為默認(rèn)格式
if [ -z "$CATALINA_OUT" ] ; then
CATALINA_OUT="$CATALINA_BASE"/logs/catalina.out
fi
if [ -z "$CATALINA_TMPDIR" ] ; then
# Define the java.io.tmpdir to use for Catalina
CATALINA_TMPDIR="$CATALINA_BASE"/temp
fi
# Bugzilla 37848: When no TTY is available, don't output to console
#獲取當(dāng)前shell運(yùn)行的終端設(shè)備
have_tty=0
if [ "`tty`" != "not a tty" ]; then
have_tty=1
fi
# For Cygwin, switch paths to Windows format before running java
if $cygwin; then
JAVA_HOME=`cygpath --absolute --windows "$JAVA_HOME"`
JRE_HOME=`cygpath --absolute --windows "$JRE_HOME"`
CATALINA_HOME=`cygpath --absolute --windows "$CATALINA_HOME"`
CATALINA_BASE=`cygpath --absolute --windows "$CATALINA_BASE"`
CATALINA_TMPDIR=`cygpath --absolute --windows "$CATALINA_TMPDIR"`
CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
JAVA_ENDORSED_DIRS=`cygpath --path --windows "$JAVA_ENDORSED_DIRS"`
fi
# Set juli LogManager config file if it is present and an override has not been issued
#確認(rèn)$LOGGING_CONFIG變量
if [ -z "$LOGGING_CONFIG" ]; then
if [ -r "$CATALINA_BASE"/conf/logging.properties ]; then
LOGGING_CONFIG="-Djava.util.logging.config.file=$CATALINA_BASE/conf/logging.properties"
else
# Bugzilla 45585
LOGGING_CONFIG="-Dnop"
fi
fi
#確認(rèn)$LOGGING_MANAGER變量
if [ -z "$LOGGING_MANAGER" ]; then
JAVA_OPTS="$JAVA_OPTS -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"
else
JAVA_OPTS="$JAVA_OPTS $LOGGING_MANAGER"
fi
# ----- Execute The Requested Command -----------------------------------------
# Bugzilla 37848: only output this if we have a TTY
#正常情況下have_tty=1
if [ $have_tty -eq 1 ]; then
echo "Using CATALINA_BASE: $CATALINA_BASE"
echo "Using CATALINA_HOME: $CATALINA_HOME"
echo "Using CATALINA_TMPDIR: $CATALINA_TMPDIR"
if [ "$1" = "debug" ] ; then
echo "Using JAVA_HOME: $JAVA_HOME"
else
echo "Using JRE_HOME: $JRE_HOME"
fi
echo "Using CLASSPATH: $CLASSPATH"
#以下這句判斷設(shè)置的$CATALINA_PID變量如果不存在，則顯示"Using CATALINA_PID: $CATALINA_PID"，如果存在則不顯示
if [ ! -z "$CATALINA_PID" ]; then
echo "Using CATALINA_PID: $CATALINA_PID"
fi
fi
#以上就是在啟動(dòng)tomcat是輸出的環(huán)境變量信息
#
#獲取第一次參數(shù)，jpda在后面的說明為：jpda start Start Catalina under JPDA debugger
if [ "$1" = "jpda" ] ; then
if [ -z "$JPDA_TRANSPORT" ]; then
JPDA_TRANSPORT="dt_socket"
fi
if [ -z "$JPDA_ADDRESS" ]; then
JPDA_ADDRESS="8000"
fi
if [ -z "$JPDA_SUSPEND" ]; then
JPDA_SUSPEND="n"
fi
if [ -z "$JPDA_OPTS" ]; then
JPDA_OPTS="-agentlib:jdwp=transport=$JPDA_TRANSPORT,address=$JPDA_ADDRESS,server=y,suspend=$JPDA_SUSPEND"
fi
CATALINA_OPTS="$CATALINA_OPTS $JPDA_OPTS"
shift
fi
#JPDA 模式是開啟遠(yuǎn)程debug模式，端口就是JPDA_ADDRESS,生產(chǎn)環(huán)境用不到，不去深入
#這個(gè)是debug模式
#值得注意的是變量$_RUNJDB，居然在全文沒有找到賦值的語(yǔ)句。
#從這邊開始就注意了，里面的if-fi判斷很多，一定要先調(diào)好格式再看
if [ "$1" = "debug" ] ; then
if $os400; then
echo "Debug command not available on OS400"
exit 1
else
shift
if [ "$1" = "-security" ] ; then
if [ $have_tty -eq 1 ]; then
echo "Using Security Manager"
fi
shift
exec "$_RUNJDB" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-sourcepath "$CATALINA_HOME"/../../java \
-Djava.security.manager \
-Djava.security.policy=="$CATALINA_BASE"/conf/catalina.policy \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start
else
exec "$_RUNJDB" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-sourcepath "$CATALINA_HOME"/../../java \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start
fi
fi
#上面語(yǔ)句是適配AIX環(huán)境的，不做解讀
#當(dāng)參數(shù)是debug時(shí)
elif [ "$1" = "run" ]; then
shift
#當(dāng)使用shift命令之后，原來(lái)的$2會(huì)變成$1，并且原有的$1變得不可用，通過$#命令獲得的參數(shù)個(gè)數(shù)也會(huì)少1
#這樣就可以使用$1獲取第二個(gè)參數(shù)
if [ "$1" = "-security" ] ; then
if [ $have_tty -eq 1 ]; then
echo "Using Security Manager"
fi
shift
#作廢掉前兩個(gè)參數(shù)
exec "$_RUNJAVA" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-Djava.security.manager \
-Djava.security.policy=="$CATALINA_BASE"/conf/catalina.policy \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start
else
exec "$_RUNJAVA" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start
#這個(gè)命令其實(shí)就是java命令，指定org.apache.catalina.startup.Bootstrap 這個(gè)class文件，$@和"start"作用類似于傳參到前面的安格class里
fi
#正式進(jìn)入啟動(dòng)的過程啦~
elif [ "$1" = "start" ] ; then
if [ ! -z "$CATALINA_PID" ]; then
#test –z 字符串 字符串的長(zhǎng)度為零 ,判斷這個(gè)變量或者文件內(nèi)有數(shù)據(jù)
if [ -f "$CATALINA_PID" ]; then
#-f 該『文件名』是否為文件(file)？(常用)
if [ -s "$CATALINA_PID" ]; then
#-s 偵測(cè)該文件名是否為『非空白文件』？
echo "Existing PID file found during start."
if [ -r "$CATALINA_PID" ]; then
#-r 偵測(cè)該文件名是否具有『可讀』的屬性？
#以上if語(yǔ)句主要判斷這個(gè)$CATALINA_PID，是否能正常可讀
PID=`cat "$CATALINA_PID"`
ps -p $PID >/dev/null 2>&1
if [ $? -eq 0 ] ; then
#判斷這個(gè)ＰＩＤ現(xiàn)在有沒有被占用，有就輸出這個(gè)tomcat依舊在運(yùn)行，退出
#上面這段語(yǔ)句功能非常好，可以判斷出這個(gè)PID是否還在運(yùn)行
echo "Tomcat appears to still be running with PID $PID. Start aborted."
exit 1
else
echo "Removing/clearing stale PID file."
rm -f "$CATALINA_PID" >/dev/null 2>&1
#刪除了這個(gè)$CATALINA_PID文件
if [ $? != 0 ]; then
if [ -w "$CATALINA_PID" ]; then
#-w 偵測(cè)該文件名是否具有『可寫』的屬性？
cat /dev/null > "$CATALINA_PID"
#清空$CATALINA_PID文件
else
#如果不具有可寫權(quán)限，則輸出信息，退出
echo "Unable to remove or clear stale PID file. Start aborted."
exit 1
fi
fi
fi
else
#如果"$CATALINA_PID"沒有可讀權(quán)限，任然輸出信息退出。
echo "Unable to read PID file. Start aborted."
exit 1
fi
else
#"$CATALINA_PID"是空白文件
rm -f "$CATALINA_PID" >/dev/null 2>&1
#強(qiáng)制刪除$CATALINA_PID文件
if [ $? != 0 ]; then
#成功則進(jìn)行判斷，沒有讀權(quán)限則退出腳本
if [ ! -w "$CATALINA_PID" ]; then
echo "Unable to remove or write to empty PID file. Start aborted."
exit 1
fi
fi
fi
fi
fi
#這段語(yǔ)句，主要目的就是清空$CATALINA_PID文件，如果出現(xiàn)不可讀寫，則輸出信息退出
shift
#作廢掉前面參數(shù)，$1將表示第二個(gè)參數(shù)
touch "$CATALINA_OUT"
#創(chuàng)建$CATALINA_OUT變量路徑文件
if [ "$1" = "-security" ] ; then
#如果第二個(gè)參數(shù)是-security
if [ $have_tty -eq 1 ]; then
echo "Using Security Manager"
fi
shift
"$_RUNJAVA" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-Djava.security.manager \
-Djava.security.policy=="$CATALINA_BASE"/conf/catalina.policy \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start \
>> "$CATALINA_OUT" 2>&1 &
else
#我們平時(shí)執(zhí)行啟動(dòng)tomcat核心就是這一句了
#
"$_RUNJAVA" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" start \
>> "$CATALINA_OUT" 2>&1 &
#從&可以看出啟動(dòng)的命令在后臺(tái)啟動(dòng)
fi
if [ ! -z "$CATALINA_PID" ]; then
#判斷CATALINA_PID如果不是空字符，則將Shell最后運(yùn)行的后臺(tái)Process的PID 傳給$CATALINA_PID
echo $! > "$CATALINA_PID"
#在使用命令運(yùn)行進(jìn)程至后臺(tái)時(shí)，可以使用$!抓取前面啟動(dòng)運(yùn)行在后臺(tái)進(jìn)程的進(jìn)程號(hào)
fi
fi
#下面開始了tomcat停止模塊了
elif [ "$1" = "stop" ] ; then
shift
SLEEP=5
if [ ! -z "$1" ]; then
echo $1 | grep "[^0-9]" >/dev/null 2>&1
if [ $? -gt 0 ]; then
SLEEP=$1
shift
fi
fi
#上面語(yǔ)句主要是判斷停止語(yǔ)句執(zhí)行到此時(shí)，設(shè)定幾秒后再執(zhí)行停止語(yǔ)句
#用來(lái)配合stop n
FORCE=0
if [ "$1" = "-force" ]; then
shift
FORCE=1
fi
#如果參數(shù)中使用了-force，則FORCE=1
if [ ! -z "$CATALINA_PID" ]; then
#$CATALINA_PID文件不是非空
if [ -f "$CATALINA_PID" ]; then
if [ -s "$CATALINA_PID" ]; then
kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1
#kill -0 pid 不發(fā)送任何信號(hào)，但是系統(tǒng)會(huì)進(jìn)行錯(cuò)誤檢查。
if [ $? -gt 0 ]; then
echo "PID file found but no matching process was found. Stop aborted."
exit 1
fi
else
echo "PID file is empty and has been ignored."
fi
else
echo "\$CATALINA_PID was set but the specified file does not exist. Is Tomcat running? Stop aborted."
exit 1
fi
fi
#以上腳本是進(jìn)行停止命令檢錯(cuò)的，如果可能停止不了，則可以直接報(bào)錯(cuò)
"$_RUNJAVA" $JAVA_OPTS \
-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \
-Dcatalina.base="$CATALINA_BASE" \
-Dcatalina.home="$CATALINA_HOME" \
-Djava.io.tmpdir="$CATALINA_TMPDIR" \
org.apache.catalina.startup.Bootstrap "$@" stop
#這個(gè)就是停止腳本的核心命令了
if [ ! -z "$CATALINA_PID" ]; then
if [ -f "$CATALINA_PID" ]; then
while [ $SLEEP -ge 0 ]; do
kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1
if [ $? -gt 0 ]; then
rm -f "$CATALINA_PID" >/dev/null 2>&1
if [ $? != 0 ]; then
if [ -w "$CATALINA_PID" ]; then
cat /dev/null > "$CATALINA_PID"
else
echo "Tomcat stopped but the PID file could not be removed or cleared."
fi
fi
break
fi
if [ $SLEEP -gt 0 ]; then
sleep 1
fi
if [ $SLEEP -eq 0 ]; then
if [ $FORCE -eq 0 ]; then
echo "Tomcat did not stop in time. PID file was not removed."
fi
fi
SLEEP=`expr $SLEEP - 1 `
done
fi
fi
#上段語(yǔ)句主要是清空$CATALINA_PID
#值得注意的是，生產(chǎn)環(huán)境偶爾不加-force選項(xiàng)，tomcat有時(shí)無(wú)法停止下來(lái)
#如果參數(shù)帶"-force" ，則強(qiáng)制kill掉tomcat
if [ $FORCE -eq 1 ]; then
if [ -z "$CATALINA_PID" ]; then
echo "Kill failed: \$CATALINA_PID not set"
else
if [ -f "$CATALINA_PID" ]; then
PID=`cat "$CATALINA_PID"`
echo "Killing Tomcat with the PID: $PID"
kill -9 $PID
#強(qiáng)制執(zhí)行的核心命令
rm -f "$CATALINA_PID" >/dev/null 2>&1
if [ $? != 0 ]; then
echo "Tomcat was killed but the PID file could not be removed."
fi
fi
fi
fi
#查看版本參數(shù)
elif [ "$1" = "version" ] ; then
"$_RUNJAVA" \
-classpath "$CATALINA_HOME/lib/catalina.jar" \
org.apache.catalina.util.ServerInfo
else
echo "Usage: catalina.sh ( commands ... )"
echo "commands:"
if $os400; then
echo " debug Start Catalina in a debugger (not available on OS400)"
echo " debug -security Debug Catalina with a security manager (not available on OS400)"
else
echo " debug Start Catalina in a debugger"
echo " debug -security Debug Catalina with a security manager"
fi
echo " jpda start Start Catalina under JPDA debugger"
echo " run Start Catalina in the current window"
echo " run -security Start in the current window with security manager"
echo " start Start Catalina in a separate window"
echo " start -security Start in a separate window with security manager"
echo " stop Stop Catalina, waiting up to 5 seconds for the process to end"
echo " stop n Stop Catalina, waiting up to n seconds for the process to end"
echo " stop -force Stop Catalina, wait up to 5 seconds and then use kill -KILL if still running"
echo " stop n -force Stop Catalina, wait up to n seconds and then use kill -KILL if still running"
echo " version What version of tomcat are you running?"
echo "Note: Waiting for the process to end and use of the -force option require that \$CATALINA_PID is defined"
exit 1
fi總結(jié)下，catalina.sh腳本使用了大量的判斷，使用if作為參數(shù)的輸入判斷，核心的啟動(dòng)命令其實(shí)就是java命令。如果在發(fā)生tomcat啟動(dòng)異常，大家就可以排查時(shí)在catalina.sh完成時(shí)出現(xiàn)問題，還是catalina.sh啟動(dòng)后出現(xiàn)異常，如果有想要更加深入的小伙伴，可以學(xué)習(xí)下java，會(huì)在JVM調(diào)優(yōu)和排障上會(huì)走的更遠(yuǎn)。
