startup.sh與catalina.sh只是啟動指令碼，通過環境變數與指令碼所在目錄確定java的啟動引數來正確啟動tomcat, 從引數可以找到啟動類是org.apache.catalina.startup.Bootstrap裡的main方法

指令碼中常用判斷
if [ -z “$UMASK” ] 類似這樣就是UMASK環境變數不存在時設定初始化

if [ -r “$CATALINA_HOME”/bin/setclasspath.sh ] 這是判斷檔案存在且可讀

if [ -n “$JAVA_ENDORSED_DIRS” ] 存在環境變數時處理

if [ -d “$CATALINA_HOME/endorsed” ] 是目錄處理

while [ -h “$PRG” ] 是軟連線處理

dirname “$PRG” 取得檔案所在目錄，PRG問檔案

列印啟動引數
在catalina.sh的最後處理start引數那裡，新增一系列的echo 列印輸出引數

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 "[email protected]" start \
      >> "$CATALINA_OUT" 2>&1 "&"

  else
    echo "_NOHUP:" $_NOHUP
    echo "_RUNJAVA:" $_RUNJAVA
    echo "LOGGING_CONFIG:" $LOGGING_CONFIG
    echo "LOGGING_MANAGER:" $LOGGING_MANAGER
    echo "JAVA_OPTS:" $JAVA_OPTS
    echo "CATALINA_OPTS:" $CATALINA_OPTS
    echo "ENDORSED_PROP:" $ENDORSED_PROP
    echo "JAVA_ENDORSED_DIRS:" $JAVA_ENDORSED_DIRS
    echo "CLASSPATH:" $CLASSPATH
    echo "CATALINA_BASE:" $CATALINA_BASE
    echo "CATALINA_HOME:" $CATALINA_HOME
    echo "CATALINA_TMPDIR:" $CATALINA_TMPDIR
    echo "CATALINA_OUT:" $CATALINA_OUT
    echo "print start parameters"
    exit 0
    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="\"$CATALINA_TMPDIR\"" \
      org.apache.catalina.startup.Bootstrap "[email protected]" start \
      >> "$CATALINA_OUT" 2>&1 "&"

  fi

  if [ ! -z "$CATALINA_PID" ]; then
    echo $! > "$CATALINA_PID"
  fi

  echo "Tomcat started."

elif [ "$1" = "stop" ] ; then

得到引數後，可以自己在命令列直接 java 組裝引數 執行tomcat

//這是組裝引數的最後，[email protected]表示所有傳給catalina.sh的引數
//startup.sh傳給catalina.sh start  catalina.sh在處理了第一個引數start
後使用shift，移除了第一個引數，所以下面不會有兩個start
org.apache.catalina.startup.Bootstrap "[email protected]" start \
      >> "$CATALINA_OUT" 2>&1 "&"

startup.sh 就是找到catalina.sh的目錄，並加引數start執行

./catalina.sh start 因為執行的命令是: java 引數 & 所以會後臺執行
./catalina.sh run 可以在終端執行，看日誌
./catalina.sh 沒有引數列印幫助文件

下面是我整理的啟動引數，mac系統，路徑可能需要修改，umask值修改

java -Djava.util.logging.config.file=/Users/Downloads/apache-tomcat-9.0.11/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 -Dignore.endorsed.dirs="" -classpath "/Users/Downloads/apache-tomcat-9.0.11/bin/bootstrap.jar:/Users/Downloads/apache-tomcat-9.0.11/bin/tomcat-juli.jar" -Dcatalina.base="/Users/Downloads/apache-tomcat-9.0.11" -Dcatalina.home="/Users/Downloads/apache-tomcat-9.0.11" -Djava.io.tmpdir="/Users/Downloads/apache-tomcat-9.0.11/temp" org.apache.catalina.startup.Bootstrap start >>/Users/Downloads/apache-tomcat-9.0.11/logs/catalina.out 2>&1

自定義環境變數，可以編寫setenv.sh，放到CATALINA_BASE/bin下面，catalina.sh啟動會載入，比如要載入的類jar包等等，全域性

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