Tomcat 的啟動文件 catalina.sh shell腳本詳解

接上一篇文章：我們啟動tomcat下的start.sh文件，shell腳本到底做了什么呢？在上一篇文章最后，start.sh 最終調用了 catalina.sh 腳本（調用命令為：exec /usr/local/apache-tomcat-9.0.21/bin/catalina.sh start "$@"）；那么catalina.sh 具體干了什么呢？

代碼塊：

# OS specific support.  $var _must_ be set to either true or false.
cygwin=false
darwin=false
os400=false
hpux=false
case "`uname`" in
CYGWIN*) cygwin=true;;
Darwin*) darwin=true;;
OS400*) os400=true;;
HP-UX*) hpux=true;;
esac
resolve links - $0 may be a softlink
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

    
    
   
   
           

   
   
  
  
          

上述這一段代碼，設定了一些變量， 並通過case判斷根據服務器操作系統的不同，設置不同的參數值。通過while循環判斷，獲取catalina.sh的絕對路徑（非鏈接），賦值給PRG。在服務器上執行uname為Linux。比如我的tomcat的catalina.sh的絕對路徑為/usr/local/apache-tomcat-9.0.21/bin/catalina.sh。此時，變量情況為：

cygwin=false
darwin=false
os400=false
hpux=false
PRG=/usr/local/apache-tomcat-9.0.21/bin/catalina.sh

    
    
   
   
           

   
   
  
  
          

代碼塊：

# 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"
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=
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

    
    
   
   
           

   
   
  
  
          

上述代碼，通過-z判斷變量CATALINA_HOME與CATALINA_BASE是否已經設置；若未設置，則設定默認值。默認情況下，bin目錄下默認是沒有setenv.sh文件。所以上述代碼執行后，變量變動情況如下：

PRGDIR=/usr/local/apache-tomcat-9.0.21/bin
CATALINA_HOME=/usr/local/apache-tomcat-9.0.21
CATALINA_BASE=/usr/local/apache-tomcat-9.0.21
CLASSPATH=

    
    
   
   
           

   
   
  
  
          

代碼塊：

# 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
Ensure that neither CATALINA_HOME nor CATALINA_BASE contains a colon
as this is used as the separator in the classpath and Java provides no
mechanism for escaping if the same character appears in the path.
case $CATALINA_HOME in
 :) echo "Using CATALINA_HOME: $CATALINA_HOME";
 echo "Unable to start as CATALINA_HOME contains a colon (😃 character";
 exit 1;
 esac
 case $CATALINA_BASE in
 :) echo "Using CATALINA_BASE: $CATALINA_BASE";
 echo "Unable to start as CATALINA_BASE contains a colon (😃 character";
 exit 1;
 esac

    
    
   
   
           

   
   
  
  
          

上述代碼，由於$cygwin=false，跳過if判斷。接下來兩個case通過$CATALINA_HOME與$CATALINA_BASE的值是否包含：判斷服務器是否設置了環境變量。若系統設置的環境變量，會給出提示，並退出執行腳本。由於服務器沒有CATALINA的環境變量設置，故此時無變量變化。
代碼塊：

# 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 $os400; then
-r will Only work on the os400 if the files are:
1. owned by the user
2. owned by the PRIMARY group of the user
this will not work if the user belongs in secondary groups
. "$CATALINA_HOME"/bin/setclasspath.sh
 else
 if [ -r "$CATALINA_HOME"/bin/setclasspath.sh ]; then
 . "$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

    
    
   
   
           

   
   
  
  
          

由於$os400=false，所以第一段if...else...跳過，第二段if...else...進入else 。當setclasspath.sh文件可讀時，執行該文件，否則給出提示，並退出腳本。
注：關於setclasspath.sh到底在干嘛，我們下次再詳述。 此時變量無變化。
代碼塊：

# Add on extra jar files to CLASSPATH
if [ ! -z "$CLASSPATH" ] ; then
  CLASSPATH="$CLASSPATH":
fi
CLASSPATH="$CLASSPATH""$CATALINA_HOME"/bin/bootstrap.jar
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
Add tomcat-juli.jar to classpath
tomcat-juli.jar can be over-ridden per instance
if [ -r "$CATALINA_BASE/bin/tomcat-juli.jar" ] ; then
 CLASSPATH=$CLASSPATH:$CATALINA_BASE/bin/tomcat-juli.jar
 else
 CLASSPATH=$CLASSPATH:$CATALINA_HOME/bin/tomcat-juli.jar
 fi

    
    
   
   
           

   
   
  
  
          

上述代碼，對一些變量進行簡單的判斷，根據情況賦值，此時變量變化情況為：

CLASSPATH= --> /usr/local/apache-tomcat-9.0.21/bin/bootstrap.jar
CATALINA_OUT=/usr/local/apache-tomcat-9.0.21/logs/catalina.out
CATALINA_TMPDIR=/usr/local/apache-tomcat-9.0.21/temp
CLASSPATH=/usr/local/apache-tomcat-9.0.21/bin/bootstrap.jar --> /usr/local/apache-tomcat-9.0.21/bin/bootstrap.jar:/usr/local/apache-tomcat-9.0.21/bin/tomcat-juli.jar

    
    
   
   
           

   
   
  
  
          

代碼塊：

# Bugzilla 37848: When no TTY is available, don't output to console
have_tty=0
if [ -t 1 ]; 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 "$CLASSPATH"
 [ -n "$JAVA_ENDORSED_DIRS" ] && JAVA_ENDORSED_DIRS=cygpath --path --windows "$JAVA_ENDORSED_DIRS"
 fi
if [ -z "$JSSE_OPTS" ] ; then
 JSSE_OPTS="-Djdk.tls.ephemeralDHKeySize=2048"
 fi
 JAVA_OPTS="$JAVA_OPTS $JSSE_OPTS"
Register custom URL handlers
Do this here so custom URL handles (specifically 'war:...') can be used in the security policy
JAVA_OPTS="$JAVA_OPTS -Djava.protocol.handler.pkgs=org.apache.catalina.webresources"
Set juli LogManager config file if it is present and an override has not been issued
if [ -z "$LOGGING_CONFIG" ]; then
 if [ -r "$CATALINA_BASE"/conf/logging.properties ]; then
 LOGGING_CONFIG="-Djava.util.logging.config.file=$CATALINA_BASE/conf/logging.properties"
 else
 # Bugzilla 45585
 LOGGING_CONFIG="-Dnop"
 fi
 fi
if [ -z "$LOGGING_MANAGER" ]; then
 LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"
 fi
Set UMASK unless it has been overridden
if [ -z "$UMASK" ]; then
 UMASK="0027"
 fi
 umask $UMASK

    
    
   
   
           

   
   
  
  
          

上述代碼， [ -t 1 ]=true, $cygwin=false，而后是一些變量的判斷。此時變量的變化為：

have_tty=1
JSSE_OPTS="-Djdk.tls.ephemeralDHKeySize=2048"
JAVA_OPTS="-Djdk.tls.ephemeralDHKeySize=2048"
JAVA_OPTS="-Djdk.tls.ephemeralDHKeySize=2048 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources"
LOGGING_CONFIG="-Djava.util.logging.config.file=/usr/local/apache-tomcat-9.0.21/conf/logging.properties"
LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"
UMASK="0027"

    
    
   
   
           

   
   
  
  
          

代碼塊：

# Java 9 no longer supports the java.endorsed.dirs
# system property. Only try to use it if
# JAVA_ENDORSED_DIRS was explicitly set
# or CATALINA_HOME/endorsed exists.
ENDORSED_PROP=ignore.endorsed.dirs
if [ -n "$JAVA_ENDORSED_DIRS" ]; then
    ENDORSED_PROP=java.endorsed.dirs
fi
if [ -d "$CATALINA_HOME/endorsed" ]; then
    ENDORSED_PROP=java.endorsed.dirs
fi
Make the umask available when using the org.apache.catalina.security.SecurityListener
JAVA_OPTS="$JAVA_OPTS -Dorg.apache.catalina.security.SecurityListener.UMASK=umask"
if [ -z "$USE_NOHUP" ]; then
 if $hpux; then
 USE_NOHUP="true"
 else
 USE_NOHUP="false"
 fi
 fi
 unset _NOHUP
 if [ "$USE_NOHUP" = "true" ]; then
 _NOHUP="nohup"
 fi
Add the JAVA 9 specific start-up parameters required by Tomcat
JDK_JAVA_OPTIONS="$JDK_JAVA_OPTIONS --add-opens=java.base/java.lang=ALL-UNNAMED"
 JDK_JAVA_OPTIONS="$JDK_JAVA_OPTIONS --add-opens=java.base/java.io=ALL-UNNAMED"
 JDK_JAVA_OPTIONS="$JDK_JAVA_OPTIONS --add-opens=java.rmi/sun.rmi.transport=ALL-UNNAMED"
 export JDK_JAVA_OPTIONS

    
    
   
   
           

   
   
  
  
          

上述代碼，[ -n "$JAVA_ENDORSED_DIRS" ]=falase, [ -d "$CATALINA_HOME/endorsed" ]=false， [ -z "$USE_NOHUP" ]=true，，此時變量變化如下：

JAVA_OPTS="-Djdk.tls.ephemeralDHKeySize=2048 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources -Dorg.apache.catalina.security.SecurityListener.UMASK=0027"
USE_NOHUP="false"
JDK_JAVA_OPTIONS="--add-opens=java.base/java.lang=ALL-UNNAMED"
JDK_JAVA_OPTIONS="--add-opens=java.base/java.io=ALL-UNNAMED"
JDK_JAVA_OPTIONS="--add-opens=java.rmi/sun.rmi.transport=ALL-UNNAMED"

    
    
   
   
           

   
   
  
  
          

代碼塊：

# ----- Execute The Requested Command -----------------------------------------
Bugzilla 37848: only output this if we have a TTY
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: $CLASSPATH"
 if [ ! -z "$CATALINA_PID" ]; then
 echo "Using CATALINA_PID: $CATALINA_PID"
 fi
 fi

    
    
   
   
           

   
   
  
  
          

上述代碼沒有做什么操作，只是打印了一些信息而已。
調用此腳本的外部參數為start，故下述只看 [ $1 = start ]的代碼塊：

if [ "$1" = "jpda" ] ; then
略
fi
if [ "$1" = "debug" ] ; then
略
elif [ "$1" = "run" ]; then
略
elif [ "$1" = "start" ] ; then
if [ ! -z "$CATALINA_PID" ]; then
 if [ -f "$CATALINA_PID" ]; then
 if [ -s "$CATALINA_PID" ]; then
 echo "Existing PID file found during start."
 if [ -r "$CATALINA_PID" ]; then
 PID=cat "$CATALINA_PID"
 ps -p $PID >/dev/null 2>&1
 if [ $? -eq 0 ] ; then
 echo "Tomcat appears to still be running with PID $PID. Start aborted."
 echo "If the following process is not a Tomcat process, remove the PID file and try again:"
 ps -f -p $PID
 exit 1
 else
 echo "Removing/clearing stale PID file."
 rm -f "$CATALINA_PID" >/dev/null 2>&1
 if [ $? != 0 ]; then
 if [ -w "$CATALINA_PID" ]; then
 cat /dev/null > "$CATALINA_PID"
 else
 echo "Unable to remove or clear stale PID file. Start aborted."
 exit 1
 fi
 fi
 fi
 else
 echo "Unable to read PID file. Start aborted."
 exit 1
 fi
 else
 rm -f "$CATALINA_PID" >/dev/null 2>&1
 if [ $? != 0 ]; then
 if [ ! -w "$CATALINA_PID" ]; then
 echo "Unable to remove or write to empty PID file. Start aborted."
 exit 1
 fi
 fi
 fi
 fi
 fi
shift
 touch "$CATALINA_OUT"
 if [ "$1" = "-security" ] ; then
 if [ $have_tty -eq 1 ]; then
 echo "Using Security Manager"
 fi
 shift
 eval $_NOHUP ""$_RUNJAVA"" ""$LOGGING_CONFIG"" $LOGGING_MANAGER $JAVA_OPTS $CATALINA_OPTS 
 -D$ENDORSED_PROP=""$JAVA_ENDORSED_DIRS"" 
 -classpath ""$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
 eval $_NOHUP ""$_RUNJAVA"" ""$LOGGING_CONFIG"" $LOGGING_MANAGER $JAVA_OPTS $CATALINA_OPTS 
 -D$ENDORSED_PROP=""$JAVA_ENDORSED_DIRS"" 
 -classpath ""$CLASSPATH"" 
 -Dcatalina.base=""$CATALINA_BASE"" 
 -Dcatalina.home=""$CATALINA_HOME"" 
 -Djava.io.tmpdir=""$CATALINA_TMPDIR"" 
 org.apache.catalina.startup.Bootstrap "$@" start 
 >> "$CATALINA_OUT" 2>&1 "&"
fi
if [ ! -z "$CATALINA_PID" ]; then
 echo $! > "$CATALINA_PID"
 fi
echo "Tomcat started."
 elif [ "$1" = "stop" ] ; then
 略
 elif [ "$1" = "configtest" ] ; then
 略
 elif [ "$1" = "version" ] ; then
 略
 else
 略
 fi

    
    
   
   
           

   
   
  
  
          

上述非start外部傳參的判斷條件省略了。[ "$1" = "start" ]=true, [ ! -z "$CATALINA_PID" ]=false，此時代碼走到 shift這里，由於只有一個外部傳參start,故 [ "$1" = "-security" ]=false，此時進入 else 分支，執行下述命令：

 eval $_NOHUP "\"$_RUNJAVA\"" "\"$LOGGING_CONFIG\"" $LOGGING_MANAGER $JAVA_OPTS $CATALINA_OPTS \
      -D$ENDORSED_PROP="\"$JAVA_ENDORSED_DIRS\"" \
      -classpath "\"$CLASSPATH\"" \
      -Dcatalina.base="\"$CATALINA_BASE\"" \
      -Dcatalina.home="\"$CATALINA_HOME\"" \
      -Djava.io.tmpdir="\"$CATALINA_TMPDIR\"" \
      org.apache.catalina.startup.Bootstrap "$@" start \
      >> "$CATALINA_OUT" 2>&1 "&"
注：從setclasspath.sh得變量
_RUNJAVA=/usr/java/jdk1.8.0_91/bin/java
_RUNJDB=/usr/java/jdk1.8.0_91/bin/jdb
上述命令，將變量替換掉，為：
/usr/java/jdk1.8.0_91/bin/java
 -Djava.util.logging.config.file=/usr/local/apache-tomcat-9.0.21/conf/logging.properties\
 -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
 -Djdk.tls.ephemeralDHKeySize=2048 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources -Dorg.apache.catalina.security.SecurityListener.UMASK=0027 
 -D$ENDORSED_PROP=
 -classpath /usr/local/apache-tomcat-9.0.21/bin/bootstrap.jar:/usr/local/apache-tomcat-9.0.21/bin/tomcat-juli.jar
 -Dcatalina.base=/usr/local/apache-tomcat-9.0.21 
 -Dcatalina.home=/usr/local/apache-tomcat-9.0.21 
 -Djava.io.tmpdir=/usr/local/apache-tomcat-9.0.21/temp 
 org.apache.catalina.startup.Bootstrap start 
 >> /usr/local/apache-tomcat-9.0.21/logs/catalina.out 2>&1 &

    
    
   
   
           

   
   
  
  
          

所以tomcat執行start.sh 腳本時，通常情況下 就是上述這么一個命令。你可以直接在命令行執行此命令：

[root@test-cdh conf]# /usr/java/jdk1.8.0_91/bin/java -Djava.util.logging.config.file=/usr/local/apache-tomcat-9.0.21/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djdk.tls.ephemeralDHKeySize=2048 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources -Dorg.apache.catalina.security.SecurityListener.UMASK=0027 -D= -classpath /usr/local/apache-tomcat-9.0.21/bin/bootstrap.jar:/usr/local/apache-tomcat-9.0.21/bin/tomcat-juli.jar -Dcatalina.base=/usr/local/apache-tomcat-9.0.21 -Dcatalina.home=/usr/local/apache-tomcat-9.0.21 -Djava.io.tmpdir=/usr/local/apache-tomcat-9.0.21/temp org.apache.catalina.startup.Bootstrap start >> /usr/local/apache-tomcat-9.0.21/logs/catalina.out 2>&1 &
[1] 49852

    
    
   
   
           

   
   
  
  
          

現在是不是覺得，寫的很復雜的腳本，只是一條有較多java參數的命令而已，是不是頓時豁然開朗。

附：上述有很多判斷的語句，有一博文整理了，如下（鏈接為：https://blog.csdn.net/weixin_30367873/article/details/95135922）：

運算符	描述	示例
文件比較運算符
-e filename	如果 filename 存在，則為真	[ -e /var/log/syslog ]
-d filename	如果 filename 為目錄，則為真	[ -d /tmp/mydir ]
-f filename	如果 filename 為常規文件，則為真	[ -f /usr/bin/grep ]
-L filename	如果 filename 為符號鏈接，則為真	[ -L /usr/bin/grep ]
-r filename	如果 filename 可讀，則為真	[ -r /var/log/syslog ]
-w filename	如果 filename 可寫，則為真	[ -w /var/mytmp.txt ]
-x filename	如果 filename 可執行，則為真	[ -L /usr/bin/grep ]
filename1 -nt filename2	如果 filename1 比 filename2 新，則為真	[ /tmp/install/etc/services -nt /etc/services ]
filename1 -ot filename2	如果 filename1 比 filename2 舊，則為真	[ /boot/bzImage -ot arch/i386/boot/bzImage ]
字符串比較運算符 （請注意引號的使用，這是防止空格擾亂代碼的好方法）
-z string	如果 string 長度為零，則為真	[ -z "$myvar" ]
-n string	如果 string 長度非零，則為真	[ -n "$myvar" ]
string1 = string2	如果 string1 與 string2 相同，則為真	[ "$myvar" = "one two three" ]
string1 != string2	如果 string1 與 string2 不同，則為真	[ "$myvar" != "one two three" ]
算術比較運算符
num1 -eq num2	等於	[ 3 -eq $mynum ]
num1 -ne num2	不等於	[ 3 -ne $mynum ]
num1 -lt num2	小於	[ 3 -lt $mynum ]
num1 -le num2	小於或等於	[ 3 -le $mynum ]
num1 -gt num2	大於	[ 3 -gt $mynum ]
num1 -ge num2	大於或等於	[ 3 -ge $mynum ]

    
    
   
   
           

   
   
  
  
          

出處：https://blog.csdn.net/ck3207/article/details/100932690