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<!DOCTYPE document [
<!ENTITY project SYSTEM "project.xml">
]>
<document url="systemprops.html">
&project;
<properties>
<title>System Properties</title>
</properties>
<body>
<section name="Table of Contents">
<toc/>
</section>
<section name="Introduction">
<p>The following sections list the system properties that may be set to modify
the default Tomcat behaviour.</p>
</section>
<section name="Clustering">
<properties>
<property name="org.apache.catalina. tribes.dns_lookups">
<p>If <code>true</code>, the clustering module will attempt to use DNS to
resolve any host names provided in the cluster configuration.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
</properties>
</section>
<section name="Expression Language">
<properties>
<property name="org.apache.el.BeanELResolver. CACHE_SIZE">
<p>The number of javax.el.BeanELResolver.BeanProperties objects that will
be cached by the EL Parser.</p>
<p>If not specified, the default of <code>1000</code> will be used.</p>
</property>
<property name="org.apache.el.ExpressionBuilder. CACHE_SIZE">
<p>The number of parsed EL expressions that will be cached by the EL
Parser.</p>
<p>If not specified, the default of <code>5000</code> will be used.</p>
</property>
<property name="org.apache.el.parser. COERCE_TO_ZERO">
<p>If <code>true</code>, when coercing EL expressions to numbers
<code>""</code> and <code>null</code> will be coerced to zero as required
by the specification.</p>
<p>If not specified, the default value of <code>true</code> will be used.</p>
</property>
<property name="org.apache.el.parser. SKIP_IDENTIFIER_CHECK">
<p>If <code>true</code>, when parsing EL expressions, identifiers will not be
checked to ensure that they conform to the Java Language Specification for
Java identifiers.</p>
<p>If not specified, the default value of <code>true</code> will be used.</p>
</property>
</properties>
</section>
<section name="Jasper">
<properties>
<property name="org.apache.jasper.compiler. Generator.POOL_TAGS_WITH_EXTENDS">
<p>By default, JSPs that use their own base class via the extends
attribute of the page directive, will have Tag pooling disabled since
Jasper cannot guarantee that the necessary initialisation will have taken
place. This can have a negative impact on performance. Providing the
alternative base class calls _jspInit() from Servlet.init(), setting this
property to <code>true</code> will enable pooling with an alternative base
class. If the alternative base class does not call _jspInit() and this
property is <code>true</code>, NPEs will occur when attempting to use
tags.</p>
<p>If not specified, the default value of <code>false</code> will be used.
</p>
</property>
<property name="org.apache.jasper.compiler. Generator.VAR_EXPRESSIONFACTORY">
<p>The name of the variable to use for the expression language expression
factory.</p>
<p>If not specified, the default value of <code>_el_expressionfactory</code>
will be used.</p>
</property>
<property name="org.apache.jasper.compiler. Generator.VAR_INSTANCEMANAGER">
<p>The name of the variable to use for the instance manager factory.</p>
<p>If not specified, the default value of <code>_jsp_instancemanager</code>
will be used.</p>
</property>
<property name="org.apache.jasper.compiler. Generator.STRICT_GET_PROPERTY">
<p>If <code>true</code>, the requirement to have the object referenced in
<code>jsp:getProperty</code> action to be previously "introduced"
to the JSP processor, as specified in the chapter JSP.5.3 of JSP 2.0 and
later specifications, is enforced.</p>
<p>If not specified, the specification compliant default of <code>true</code>
will be used.</p>
</property>
<property name="org.apache.jasper.compiler. Parser.STRICT_QUOTE_ESCAPING">
<p>If <code>false</code> the requirements for escaping quotes in JSP
attributes will be relaxed so that an unescaped quote will not
cause an error.</p>
<p>If not specified, the specification compliant default of
<code>true</code> will be used.</p>
</property>
<property name="org.apache.jasper.runtime. BodyContentImpl.LIMIT_BUFFER">
<p>If <code>true</code>, any tag buffer that expands beyond
<code>org.apache.jasper.Constants.DEFAULT_TAG_BUFFER_SIZE</code> will be
destroyed and a new buffer created of the default size.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
<property name="org.apache.jasper.runtime. JspFactoryImpl.USE_POOL">
<p>If <code>true</code>, a ThreadLocal <code>PageContext</code> pool will
be used.</p>
<p>If not specified, the default value of <code>true</code> will be used.</p>
</property>
<property name="org.apache.jasper.runtime. JspFactoryImpl.POOL_SIZE">
<p>The size of the ThreadLocal <code>PageContext</code>.</p>
<p>If not specified, the default value of <code>8</code> will be used.</p>
</property>
<property name="org.apache.jasper.Constants. JSP_SERVLET_BASE">
<p>The base class of the Servlets generated from the JSPs.</p>
<p>If not specified, the default value of
<code>org.apache.jasper.runtime.HttpJspBase</code> will be used.</p>
</property>
<property name="org.apache.jasper.Constants. SERVICE_METHOD_NAME">
<p>The name of the service method called by the base class.</p>
<p>If not specified, the default value of <code>_jspService</code>
will be used.</p>
</property>
<property name="org.apache.jasper.Constants. SERVLET_CLASSPATH">
<p>The name of the ServletContext attribute that provides the classpath
for the JSP.</p>
<p>If not specified, the default value of
<code>org.apache.catalina.jsp_classpath</code> will be used.</p>
</property>
<property name="org.apache.jasper.Constants. JSP_FILE">
<p>The name of the request attribute for <code><jsp-file></code>
element of a servlet definition. If present on a request, this overrides
the value returned by <code>request.getServletPath()</code> to select the
JSP page to be executed.</p>
<p>If not specified, the default value of
<code>org.apache.catalina.jsp_file</code> will be used.</p>
</property>
<property name="org.apache.jasper.Constants. PRECOMPILE">
<p>The name of the query parameter that causes the JSP engine to just
pregenerate the servlet but not invoke it.</p>
<p>If not specified, the default value of <code>jsp_precompile</code>
will be used, as defined by JSP specification (JSP.11.4.2).</p>
</property>
<property name="org.apache.jasper.Constants. JSP_PACKAGE_NAME">
<p>The default package name for compiled jsp pages.</p>
<p>If not specified, the default value of <code>org.apache.jsp</code>
will be used.</p>
</property>
<property name="org.apache.jasper.Constants. TAG_FILE_PACKAGE_NAME">
<p>The default package name for tag handlers generated from tag files.</p>
<p>If not specified, the default value of <code>org.apache.jsp.tag</code>
will be used.</p>
</property>
<property name="org.apache.jasper.Constants. ALT_DD_ATTR">
<p>The servlet context attribute under which the alternate deployment
descriptor for this web application is stored.</p>
<p>If not specified, the
default value of <code>org.apache.catalina.deploy.alt_dd</code> will
be used.</p>
</property>
<property name="org.apache.jasper.Constants. TEMP_VARIABLE_NAME_PREFIX">
<p>Prefix to use for generated temporary variable names.</p>
<p>If not specified,
the default value of <code>_jspx_temp</code> will be used.</p>
</property>
<property name="org.apache.jasper.Constants. USE_INSTANCE_MANAGER_FOR_TAGS">
<p>If <code>true</code>, the instance manager is used to obtain tag
handler instances.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
</properties>
</section>
<section name="Security">
<properties>
<property name="org.apache.catalina.connector. RECYCLE_FACADES">
<p>If this is <code>true</code> or if a security manager is in use a new
facade object will be created for each request.</p>
<p>If not specified, the
default value of <code>false</code> will be used.</p>
</property>
<property
name="org.apache.catalina.connector. CoyoteAdapter.ALLOW_BACKSLASH">
<p>If this is <code>true</code> the '\' character will be permitted as a
path delimiter.</p>
<p>If not specified, the default value of <code>false</code>
will be used.</p>
</property>
<property
name="org.apache.tomcat.util.buf. UDecoder.ALLOW_ENCODED_SLASH">
<p>If this is <code>true</code> '%2F' and '%5C' will be permitted as path
delimiters.</p>
<p>If not specified, the default value of <code>false</code> will
be used.</p>
</property>
<property
name="org.apache.coyote. USE_CUSTOM_STATUS_MSG_IN_HEADER"><p>If this is
<code>true</code>, custom HTTP status messages will be used within HTTP
headers. If a custom message is specified that is not valid for use in an
HTTP header (as defined by RFC2616) then the custom message will be
ignored and the default message used.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
</properties>
</section>
<section name="Specification">
<properties>
<property name="org.apache.catalina. STRICT_SERVLET_COMPLIANCE">
<p>If this is <code>true</code> the following actions will occur:
<ul>
<li>any wrapped request or response object passed to an application
dispatcher will be checked to ensure that it has wrapped the original
request or response. (SRV.8.2 / SRV.14.2.5.1)
</li>
<li>a call to <code>Response.getWriter()</code> if no character encoding
has been specified will result in subsequent calls to
<code>Response.getCharacterEncoding()</code> returning
<code>ISO-8859-1</code> and the <code>Content-Type</code> response header
will include a <code>charset=ISO-8859-1</code> component. (SRV.15.2.22.1)
</li>
<li>every request that is associated with a session will cause the
session's last accessed time to be updated regardless of whether or not
the request explicitly accesses the session. (SRV.7.6)
</li>
<li>
cookies will be parsed strictly, by default v0 cookies will not work with any invalid characters.
<br/>If set to <code>false</code>, any v0 cookie with invalid character
will be switched to a v1 cookie and the value will be quoted.
</li>
<li>
the path in <code>ServletContext.getResource</code> /
<code>getResourceAsStream</code> calls must start with a "/".<br/>
If set to <code>false</code>, code like <code>getResource("myfolder/myresource.txt")</code> will work.
</li>
</ul>
</p>
<p>If this is <code>true</code> the default value will be changed for:
<ul>
<li><code>org.apache.catalina.connector.Request. ALLOW_EMPTY_QUERY_STRING</code> property</li>
</ul>
</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
<property
name="org.apache.catalina.connector. Request.ALLOW_EMPTY_QUERY_STRING">
<p>If this is <code>true</code> Tomcat will return an empty string rather
than <code>null</code> for empty query strings - i.e. query strings where
only <code>?</code> is present.</p>
<p>If not specified, the value of
<code>org.apache.catalina.STRICT_SERVLET_COMPLIANCE</code> will be used as
the default.</p>
</property>
<property
name="org.apache.catalina.session. StandardSession.ACTIVITY_CHECK">
<p>If this is <code>true</code> or if
<code>org.apache.catalina.STRICT_SERVLET_COMPLIANCE</code> is
<code>true</code> Tomcat will track the number of active requests for each
session. When determining if a session is valid, any session with at least
one active request will always be considered valid.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
<property
name="org.apache.tomcat.util.http. ServerCookie.ALLOW_EQUALS_IN_VALUE">
<p>If this is <code>true</code> Tomcat will allow '<code>=</code>'
characters when parsing unquoted cookie values. If <code>false</code>,
cookie values containing '<code>=</code>' will be terminated when the
'<code>=</code>' is encountered and the remainder of the cookie value will
be dropped.</p>
<p>If not specified, the default specification compliant value of
<code>false</code> will be used.</p>
</property>
<property
name="org.apache.tomcat.util.http. ServerCookie.ALWAYS_ADD_EXPIRES">
<p>If this is <code>true</code> Tomcat will always add an expires
parameter to a SetCookie header even for cookies with version greater than
zero. This is to work around a known IE6 and IE7 bug that causes IE to
ignore the Max-Age parameter in a SetCookie header.</p>
<p>If not specified, the default value of <code>true</code> will be used.</p>
</property>
</properties>
</section>
<section name="Sessions">
<properties>
<property name="org.apache.catalina.SESSION_COOKIE_NAME">
<p>An alternative name for the session cookie. Defaults to
<code>JSESSIONID</code>. Note that the Servlet specification requires
this to be <code>JSESSIONID</code>. You should not rely on being able to
change this.</p>
</property>
<property name="org.apache.catalina.SESSION_PARAMETER_NAME">
<p>An alternative name for the session path parameter. Defaults to
<code>jsessionid</code>. Note that the Servlet specification requires
this to be <code>jsessionid</code>. You should not rely on being able to
change this.</p>
</property>
<property name="org.apache.catalina.authenticator.
Constants.SSO_SESSION_COOKIE_NAME">
<p>An alternative name for the single sign on session cookie. Defaults to
<code>JSESSIONIDSSO</code>.</p>
</property>
</properties>
</section>
<section name="Other">
<properties>
<property name="org.apache.coyote.MAX_TRAILER_SIZE">
<p>Limits the total length of trailing headers in the last chunk of
a chunked HTTP request.
If the value is <code>-1</code>, no limit will be imposed.</p>
<p>If not specified, the default value of <code>8192</code> will be used.</p>
</property>
<property name="catalina.useNaming">
<p>If this is <code>false</code> it will override the
<code>useNaming</code> attribute for all <a href="context.html">
Context</a> elements.</p>
</property>
<property name="jvmRoute">
<p>Provides a default value for the <code>jvmRoute</code> attribute of the
<a href="engine.html">Engine</a> element. It does not override the value
configured on the <a href="engine.html">Engine</a> element.</p>
</property>
<property
name="org.apache.catalina.loader. WebappClassLoader.ENABLE_CLEAR_REFERENCES">
<p>If <code>true</code>, Tomcat attempts to null out any static or final
fields from loaded classes when a web application is stopped as a work
around for apparent garbage collection bugs and application coding errors.
</p>
<p>There have been some issues reported with log4j when this option is
<code>true</code>.</p>
<p>Applications without memory leaks using recent JVMs should operate
correctly with this option set to <code>false</code>.</p>
<p>If not specified, the default value of <code>true</code> will be used.
</p>
</property>
<property name="catalina.config">
<p>The URL for the catalina.properties configuration file.</p>
</property>
<property name="tomcat.util.buf.StringCache.byte.enabled">
<p>If <code>true</code>, the String cache is enabled for
<code>ByteChunk</code>.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
<property name="tomcat.util.buf.StringCache.char.enabled">
<p>If <code>true</code>, the String cache is enabled for
<code>CharChunk</code>.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
<property name="tomcat.util.buf.StringCache.trainThreshold">
<p>The number of times <code>toString()</code> must be called before the
cache is activated.</p>
<p>If not specified, the default value of <code>20000</code> will be used.</p>
</property>
<property name="tomcat.util.buf.StringCache.cacheSize">
<p>The size of the String cache.</p>
<p>If not specified, the default value of <code>200</code> will be used.</p>
</property>
<property name="tomcat.util.buf.StringCache.maxStringSize">
<p>The maximum length of String that will be cached.</p>
<p>If not specified, the default value of <code>128</code> will be used.</p>
</property>
<property name="org.apache.tomcat.util. http.FastHttpDateFormat.CACHE_SIZE">
<p>The size of the cache to use parsed and formatted date value.</p>
<p>If not specified, the default value of <code>1000</code> will be used.</p>
</property>
<property name="org.apache.tomcat.util. net.NioSelectorShared">
<p>If <code>true</code>, use a shared selector for servlet write/read.</p>
<p>If not specified, the default value of <code>true</code> will be used.</p>
</property>
<property name="org.apache.catalina.startup. EXIT_ON_INIT_FAILURE">
<p>If <code>true</code>, the server will exit if an exception happens
during the server initialization phase.</p>
<p>If not specified, the default value of <code>false</code> will be used.</p>
</property>
</properties>
</section>
</body>
</document>