Tomcat笔记2(启动脚本startup.bat分析)

Tomcat(7.0)的bin目录下包含startup.bat和catalina.bat，启动执行startup.bat之后，会在其中call catalina.bat执行。

starup.bat:

rem 之前的声明省略   
rem Guess CATALINA_HOME if not defined   
  
rem 确定环境变量CATALINA_HOME 被定义   
set "CURRENT_DIR=%cd%"  
if not "%CATALINA_HOME%" == "" goto gotHome   
set "CATALINA_HOME=%CURRENT_DIR%"  
if exist "%CATALINA_HOME%\bin\catalina.bat" goto okHome   
cd ..   
set "CATALINA_HOME=%cd%"  
cd "%CURRENT_DIR%"  
:gotHome   
if exist "%CATALINA_HOME%\bin\catalina.bat" goto okHome   
echo The CATALINA_HOME environment variable is not defined correctly   
echo This environment variable is needed to run this program   
goto end   
:okHome   
  
set "EXECUTABLE=%CATALINA_HOME%\bin\catalina.bat"  
  
rem Check that target executable exists   
  
rem 定义执行目标文件赋值给变量EXECUTABLE   
if exist "%EXECUTABLE%" goto okExec   
echo Cannot find "%EXECUTABLE%"  
echo This file is needed to run this program   
goto end   
:okExec   
  
rem Get remaining unshifted command line arguments and save them in the   
  
rem 参数验证及格式转换   
set CMD_LINE_ARGS=   
:setArgs   
if ""%1""=="""" goto doneSetArgs   
set CMD_LINE_ARGS=%CMD_LINE_ARGS% %1   
shift   
goto setArgs   
:doneSetArgs   
  
rem 之前都是变量验证，格式检查，参数验证等预处理   
rem 这一步才是核心   
call "%EXECUTABLE%" start %CMD_LINE_ARGS%   
  
:end

之后调用catalian.bat文件，传入参数start，如果startup中包含参数也一并传入给catalina.

rem 验证系统版本Windwos_NT   
rem Windows 2000, Windows XP, Windows Server 2003, Windows Vista, Windows Home Server, rem Windows Server 2008 and Windows 7 are based on Windows NT, although they are not branded as Windows NT.   
  
if "%OS%" == "Windows_NT" setlocal   
rem ---------------------------------------------------------------------------   
rem Start/Stop Script for the CATALINA Server   
rem   
rem Environment Variable Prequisites   
rem   
rem   CATALINA_HOME   May point at your Catalina "build" directory.   
rem   
rem   CATALINA_BASE   (Optional) Base directory for resolving dynamic portions   
rem                   of a Catalina installation.  If not present, resolves to   
rem                   the same directory that CATALINA_HOME points to.   
rem   
rem   CATALINA_OPTS   (Optional) Java runtime options used when the "start",   
rem                   or "run" command is executed.   
rem   
rem   CATALINA_TMPDIR (Optional) Directory path location of temporary directory   
rem                   the JVM should use (java.io.tmpdir).  Defaults to   
rem                   %CATALINA_BASE%\temp.   
rem   
rem   JAVA_HOME       Must point at your Java Development Kit installation.   
rem                   Required to run the with the "debug" argument.   
rem   
rem   JRE_HOME        Must point at your Java Runtime installation.   
rem                   Defaults to JAVA_HOME if empty.   
rem   
rem   JAVA_OPTS       (Optional) Java runtime options used when the "start",   
rem                   "stop", or "run" command is executed.   
rem   
rem   JAVA_ENDORSED_DIRS (Optional) Lists of of semi-colon separated directories   
rem                   containing some jars in order to allow replacement of APIs    
rem                   created outside of the JCP (i.e. DOM and SAX from W3C).    
rem                   It can also be used to update the XML parser implementation.   
rem                   Defaults to $CATALINA_HOME/endorsed.   
rem   
rem   JPDA_TRANSPORT  (Optional) JPDA transport used when the "jpda start"  
rem                   command is executed. The default is "dt_socket".   
rem   
rem   JPDA_ADDRESS    (Optional) Java runtime options used when the "jpda start"  
rem                   command is executed. The default is 8000.   
rem   
rem   JPDA_SUSPEND    (Optional) Java runtime options used when the "jpda start"  
rem                   command is executed. Specifies whether JVM should suspend   
rem                   execution immediately after startup. Default is "n".   
rem   
rem   JPDA_OPTS       (Optional) Java runtime options used when the "jpda start"  
rem                   command is executed. If used, JPDA_TRANSPORT, JPDA_ADDRESS,   
rem                   and JPDA_SUSPEND are ignored. Thus, all required jpda   
rem                   options MUST be specified. The default is:   
rem   
rem                   -agentlib:jdwp=transport=%JPDA_TRANSPORT%,   
rem                       address=%JPDA_ADDRESS%,server=y,suspend=%JPDA_SUSPEND%   
rem   
rem   LOGGING_CONFIG  (Optional) Override Tomcat's logging config file   
rem                   Example (all one line)   
rem                   set LOGGING_CONFIG="-Djava.util.logging.config.file=%CATALINA_BASE%\conf\logging.properties"  
rem   
rem   LOGGING_MANAGER (Optional) Override Tomcat's logging manager    
rem                   Example (all one line)   
rem                   set LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"  
rem   
rem   TITLE           (Optional) Specify the title of Tomcat window. The default   
rem                   TITLE is Tomcat if it's not specified.   
rem                   Example (all one line)   
rem                   set TITLE=Tomcat.Cluster#1.Server#1 [%DATE% %TIME%]   
rem   
rem   
rem   
rem $Id: catalina.bat 947837 2010-05-24 22:19:23Z kkolinko $   
rem ---------------------------------------------------------------------------   
  
rem Suppress Terminate batch job on CTRL+C   
if not ""%1"" == ""run"" goto mainEntry   
if ""%TEMP%"" == """" goto mainEntry   
if exist "%TEMP%\%~nx0.run" goto mainEntry   
echo Y>"%TEMP%\%~nx0.run"  
if not exist "%TEMP%\%~nx0.run" goto mainEntry   
echo Y>"%TEMP%\%~nx0.Y"  
call "%~f0" %* <"%TEMP%\%~nx0.Y"  
rem Use provided errorlevel   
set RETVAL=%ERRORLEVEL%   
del /Q "%TEMP%\%~nx0.Y" >NUL 2>&1   
exit /B %RETVAL%   
:mainEntry   
del /Q "%TEMP%\%~nx0.run" >NUL 2>&1   
  
rem 设定CATALINA环境变量   
rem Guess CATALINA_HOME if not defined   
set "CURRENT_DIR=%cd%"  
if not "%CATALINA_HOME%" == "" goto gotHome   
set "CATALINA_HOME=%CURRENT_DIR%"  
if exist "%CATALINA_HOME%\bin\catalina.bat" goto okHome   
cd ..   
set "CATALINA_HOME=%cd%"  
cd "%CURRENT_DIR%"  
:gotHome   
if exist "%CATALINA_HOME%\bin\catalina.bat" goto okHome   
echo The CATALINA_HOME environment variable is not defined correctly   
echo This environment variable is needed to run this program   
goto end   
:okHome   
  
rem Ensure that any user defined CLASSPATH variables are not used on startup,   
rem but allow them to be specified in setenv.bat, in rare case when it is needed.   
set CLASSPATH=   
  
rem 取得CATALINA环境变量   
rem Get standard environment variables   
if "%CATALINA_BASE%" == "" goto gotSetenvHome   
if exist "%CATALINA_BASE%\bin\setenv.bat" call "%CATALINA_BASE%\bin\setenv.bat"  
goto gotSetenvBase   
:gotSetenvHome   
if exist "%CATALINA_HOME%\bin\setenv.bat" call "%CATALINA_HOME%\bin\setenv.bat"  
:gotSetenvBase   
  
rem Get standard Java environment variables   
if exist "%CATALINA_HOME%\bin\setclasspath.bat" goto okSetclasspath   
echo Cannot find "%CATALINA_HOME%\bin\setclasspath.bat"  
echo This file is needed to run this program   
goto end   
:okSetclasspath   
set "BASEDIR=%CATALINA_HOME%"  
call "%CATALINA_HOME%\bin\setclasspath.bat" %1   
if errorlevel 1 goto end   
  
rem Add on extra jar file to CLASSPATH   
rem Note that there are no quotes as we do not want to introduce random   
rem quotes into the CLASSPATH   
if "%CLASSPATH%" == "" goto emptyClasspath   
set "CLASSPATH=%CLASSPATH%;"  
:emptyClasspath   
set "CLASSPATH=%CLASSPATH%%CATALINA_HOME%\bin\bootstrap.jar"  
  
if not "%CATALINA_BASE%" == "" goto gotBase   
set "CATALINA_BASE=%CATALINA_HOME%"  
:gotBase   
  
if not "%CATALINA_TMPDIR%" == "" goto gotTmpdir   
set "CATALINA_TMPDIR=%CATALINA_BASE%\temp"  
:gotTmpdir   
  
rem Add tomcat-juli.jar to classpath   
rem tomcat-juli.jar can be over-ridden per instance   
if not exist "%CATALINA_BASE%\bin\tomcat-juli.jar" goto juliClasspathHome   
set "CLASSPATH=%CLASSPATH%;%CATALINA_BASE%\bin\tomcat-juli.jar"  
goto juliClasspathDone   
:juliClasspathHome   
set "CLASSPATH=%CLASSPATH%;%CATALINA_HOME%\bin\tomcat-juli.jar"  
:juliClasspathDone   
  
if not "%LOGGING_CONFIG%" == "" goto noJuliConfig   
set LOGGING_CONFIG=-Dnop   
if not exist "%CATALINA_BASE%\conf\logging.properties" goto noJuliConfig   
set LOGGING_CONFIG=-Djava.util.logging.config.file="%CATALINA_BASE%\conf\logging.properties"  
:noJuliConfig   
set JAVA_OPTS=%JAVA_OPTS% %LOGGING_CONFIG%   
  
if not "%LOGGING_MANAGER%" == "" goto noJuliManager   
set LOGGING_MANAGER=-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager   
:noJuliManager   
set JAVA_OPTS=%JAVA_OPTS% %LOGGING_MANAGER%   
  
rem ----- Execute The Requested Command ---------------------------------------   
  
echo Using CATALINA_BASE:   "%CATALINA_BASE%"  
echo Using CATALINA_HOME:   "%CATALINA_HOME%"  
echo Using CATALINA_TMPDIR: "%CATALINA_TMPDIR%"  
if ""%1"" == ""debug"" goto use_jdk   
echo Using JRE_HOME:        "%JRE_HOME%"  
goto java_dir_displayed   
:use_jdk   
echo Using JAVA_HOME:       "%JAVA_HOME%"  
:java_dir_displayed   
echo Using CLASSPATH:       "%CLASSPATH%"  
  
set _EXECJAVA=%_RUNJAVA%   
set MAINCLASS=org.apache.catalina.startup.Bootstrap   
set ACTION=start   
set SECURITY_POLICY_FILE=   
set DEBUG_OPTS=   
set JPDA=   
  
if not ""%1"" == ""jpda"" goto noJpda   
set JPDA=jpda   
if not "%JPDA_TRANSPORT%" == "" goto gotJpdaTransport   
set JPDA_TRANSPORT=dt_socket   
:gotJpdaTransport   
if not "%JPDA_ADDRESS%" == "" goto gotJpdaAddress   
set JPDA_ADDRESS=8000   
:gotJpdaAddress   
if not "%JPDA_SUSPEND%" == "" goto gotJpdaSuspend   
set JPDA_SUSPEND=n   
:gotJpdaSuspend   
if not "%JPDA_OPTS%" == "" goto gotJpdaOpts   
set JPDA_OPTS=-agentlib:jdwp=transport=%JPDA_TRANSPORT%,address=%JPDA_ADDRESS%,server=y,suspend=%JPDA_SUSPEND%   
:gotJpdaOpts   
shift   
:noJpda   
  
if ""%1"" == ""debug"" goto doDebug   
if ""%1"" == ""run"" goto doRun   
if ""%1"" == ""start"" goto doStart   
if ""%1"" == ""stop"" goto doStop   
if ""%1"" == ""version"" goto doVersion   
  
rem 想到Linux下面的各种命令行的shell程序 很类似   
  
echo Usage:  catalina ( commands ... )   
echo commands:   
echo   debug             Start Catalina in a debugger   
echo   debug -security   Debug Catalina with a security manager   
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   
echo   version           What version of tomcat are you running?   
goto end   
  
rem 之前都是预处理，到这里才开始真正进行分支调用   
  
:doDebug   
shift   
set _EXECJAVA=%_RUNJDB%   
set DEBUG_OPTS=-sourcepath "%CATALINA_HOME%\..\..\java"  
if not ""%1"" == ""-security"" goto execCmd   
shift   
echo Using Security Manager   
set "SECURITY_POLICY_FILE=%CATALINA_BASE%\conf\catalina.policy"  
goto execCmd   
  
:doRun   
shift   
if not ""%1"" == ""-security"" goto execCmd   
shift   
echo Using Security Manager   
set "SECURITY_POLICY_FILE=%CATALINA_BASE%\conf\catalina.policy"  
goto execCmd   
  
:doStart   
shift   
if not "%OS%" == "Windows_NT" goto noTitle   
if "%TITLE%" == "" set TITLE=Tomcat   
set _EXECJAVA=start "%TITLE%" %_RUNJAVA%   
goto gotTitle   
:noTitle   
set _EXECJAVA=start %_RUNJAVA%   
:gotTitle   
if not ""%1"" == ""-security"" goto execCmd   
shift   
echo Using Security Manager   
set "SECURITY_POLICY_FILE=%CATALINA_BASE%\conf\catalina.policy"  
goto execCmd   
  
:doStop   
shift   
set ACTION=stop   
set CATALINA_OPTS=   
goto execCmd   
  
:doVersion   
%_EXECJAVA% -classpath "%CATALINA_HOME%\lib\catalina.jar" org.apache.catalina.util.ServerInfo   
goto end   
  
  
:execCmd   
rem Get remaining unshifted command line arguments and save them in the   
set CMD_LINE_ARGS=   
:setArgs   
if ""%1""=="""" goto doneSetArgs   
set CMD_LINE_ARGS=%CMD_LINE_ARGS% %1   
shift   
goto setArgs   
:doneSetArgs   
  
rem --------------------------------------------------------------------------------- rem   
  
rem Execute Java with the applicable properties   
rem 这里才是真正要执行的jvm命令   
if not "%JPDA%" == "" goto doJpda   
if not "%SECURITY_POLICY_FILE%" == "" goto doSecurity   
%_EXECJAVA% %JAVA_OPTS% %CATALINA_OPTS% %DEBUG_OPTS% -Djava.endorsed.dirs="%JAVA_ENDORSED_DIRS%" -classpath "%CLASSPATH%" -Dcatalina.base="%CATALINA_BASE%" -Dcatalina.home="%CATALINA_HOME%" -Djava.io.tmpdir="%CATALINA_TMPDIR%" %MAINCLASS% %CMD_LINE_ARGS% %ACTION%   
goto end   
:doSecurity   
%_EXECJAVA% %JAVA_OPTS% %CATALINA_OPTS% %DEBUG_OPTS% -Djava.endorsed.dirs="%JAVA_ENDORSED_DIRS%" -classpath "%CLASSPATH%" -Djava.security.manager -Djava.security.policy=="%SECURITY_POLICY_FILE%" -Dcatalina.base="%CATALINA_BASE%" -Dcatalina.home="%CATALINA_HOME%" -Djava.io.tmpdir="%CATALINA_TMPDIR%" %MAINCLASS% %CMD_LINE_ARGS% %ACTION%   
goto end   
:doJpda   
if not "%SECURITY_POLICY_FILE%" == "" goto doSecurityJpda   
%_EXECJAVA% %JAVA_OPTS% %CATALINA_OPTS% %JPDA_OPTS% %DEBUG_OPTS% -Djava.endorsed.dirs="%JAVA_ENDORSED_DIRS%" -classpath "%CLASSPATH%" -Dcatalina.base="%CATALINA_BASE%" -Dcatalina.home="%CATALINA_HOME%" -Djava.io.tmpdir="%CATALINA_TMPDIR%" %MAINCLASS% %CMD_LINE_ARGS% %ACTION%   
goto end   
:doSecurityJpda   
%_EXECJAVA% %JAVA_OPTS% %CATALINA_OPTS% %JPDA_OPTS% %DEBUG_OPTS% -Djava.endorsed.dirs="%JAVA_ENDORSED_DIRS%" -classpath "%CLASSPATH%" -Djava.security.manager -Djava.security.policy=="%SECURITY_POLICY_FILE%" -Dcatalina.base="%CATALINA_BASE%" -Dcatalina.home="%CATALINA_HOME%" -Djava.io.tmpdir="%CATALINA_TMPDIR%" %MAINCLASS% %CMD_LINE_ARGS% %ACTION%   
goto end   
  
:end  

其中，":label名"不代表一个过程，只是代表其本身一个程序点而已，原来总以为是个类似函数或者过程定义的东西，现在看来，它只代表自己而已，仅仅是告诉goto语句跳到这个点上。

%_EXECJAVA% %JAVA_OPTS% %CATALINA_OPTS% %DEBUG_OPTS% -Djava.endorsed.dirs="%JAVA_ENDORSED_DIRS%" -classpath "%CLASSPATH%" -Dcatalina.base="%CATALINA_BASE%" -Dcatalina.home="%CATALINA_HOME%" -Djava.io.tmpdir="%CATALINA_TMPDIR%" %MAINCLASS% %CMD_LINE_ARGS% %ACTION%  

这段代码才是jvm(对应java命令)执行的总命令行，其中传入了各种参数，即在startup.bat中调用catalina，根据传入命令(e.g. start..)选择对应入口，由于在之前已经设定好了环境变量，等各种参数检查(统称为预处理)，直到这里才是真正进行了jvm启动。

echo了一下，最终启动命令为:

start "Tomcat" "C:\Program Files\Java\jdk1.6.0_21\bin\java"  -Djava.util.logging.config.file="D:\work_ju\tomcat7.0\output\build\conf\logging.properties" -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager    -Djava.endorsed.dirs="D:\work_ju\tomcat7.0\output\build\endorsed" -classpath "D:\work_ju\tomcat7.0\output\build\bin\bootstrap.jar;D:\work_ju\tomcat7.0\output\build\bin\tomcat-juli.jar" -Djava.security.manager -Djava.security.policy=="" -Dcatalina.base="D:\work_ju\tomcat7.0\output\build" -Dcatalina.home="D:\work_ju\tomcat7.0\output\build" -Djava.io.tmpdir="D:\work_ju\tomcat7.0\output\build\temp" org.apache.catalina.startup.Bootstrap  start  

可以看到关于启动环境的各种具体配置。

set MAINCLASS=org.apache.catalina.startup.Bootstrap  

bat中此处设定了jvm的虚拟机入口，即main函数，可以看到是交由Bootstrap类进行的，它被提供给classloader加载，并执行main()。

这也类似开源框架中的load-on-startup为1的servlet，交给servlet容器给予启动。而其init方法则可类比为main函数，只是main函数是交给虚拟机启动的，而init方法是交给servlet容器，通过java反射由servlet容器进行启动。

在tomcat的web.xml文件当中，定义load-on-startup的servlet是org.apache.catalina.servlets.DefaultServlet，它只有一个子类，即WebdavServlet，根据规范，在init()方法中进行ServletContext和ServletConfig的初始化，service()起到一个选择doGet()，doPost()，doHead()等方法的分派作用，所以只在子类的WebdavServlet当中定义该方法，doGet(),doPost()的基础性工作都在父类DefaultServlet当中完成。


注：
1.CATALINA_BASE 定义：
#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.

2.关于启动命令及参数：

在tomcat启动之后，也可以通过sun提供内存查看工具jconsole查看最终启动参数和各项内存情况。