================================================================================
  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.
================================================================================

            ====================================================
            Building The Apache Tomcat @VERSION_MAJOR_MINOR@ Servlet/JSP Container
            ====================================================

This subproject contains the source code for Tomcat @VERSION_MAJOR_MINOR@, a container that
implements the Servlet 4.0, JSP 2.3, EL 3.0, WebSocket 1.1 and JASPIC 1.1
specifications from the Java Community Process <https://www.jcp.org/>.

Note: If you just need to run Apache Tomcat, it is not necessary to build
it. You may simply download a binary distribution. It is cross-platform.
Read RUNNING.txt for the instruction on how to run it.

In order to build a binary distribution version of Apache Tomcat from a
source distribution, do the following:


(1) Download and Install a Java Development Kit

 1. If the JDK is already installed, skip to (2).

 2. Download a version 8 of Java Development Kit (JDK) release (use the
    latest update available for your chosen version) from one of:

        http://www.oracle.com/technetwork/java/javase/downloads/index.html
        http://openjdk.java.net/install/index.html
        or another JDK vendor.

    Note regarding later versions of Java:

      As documented elsewhere, one of components in Apache Tomcat includes
      a private copy of the Apache Commons DBCP 2 library.

      The JDBC interfaces implemented by DBCP frequently change in non-backwards
      compatible ways between versions of the Java SE specification. Therefore,
      it is likely that DBCP 2 will only compile with the specific version of Java
      listed above and that compilation will fail if a later version of Java is
      used.

      See Apache Commons DBCP 2 project web site for more details on
      available versions of the library and its requirements,

        https://commons.apache.org/dbcp/

 3. Install the JDK according to the instructions included with the release.

 4. Set an environment variable JAVA_HOME to the pathname of the directory
    into which you installed the JDK release.


(2) Install Apache Ant version 1.9.10 or later on your computer.

 1. If Apache Ant version 1.9.10 or later is already installed on your
    computer, skip to (3).

 2. Download a binary distribution of Ant from:

        https://ant.apache.org/bindownload.cgi

 3. Unpack the binary distribution into a convenient location so that the
    Ant release resides in its own directory (conventionally named
    "apache-ant-[version]").

    For the purposes of the remainder of this document, the symbolic name
    "${ant.home}" is used to refer to the full pathname of the release
    directory.

 4. Create an ANT_HOME environment variable to point the directory
    ${ant.home}.

 5. Modify the PATH environment variable to include the directory
    ${ant.home}/bin in its list.  This makes the "ant" command line script
    available, which will be used to actually perform the build.


(3) Building Tomcat @VERSION_MAJOR_MINOR@

(3.1) Checkout or obtain the source code for Tomcat @VERSION_MAJOR_MINOR@

Clone the source using git, then checkout a specific major branch or
master for the latest code development, or download and unpack a source
package.

 *  Tomcat GitHub repository URL:

        https://github.com/apache/tomcat

 *  Source packages can be downloaded from:

        https://tomcat.apache.org/download-@VERSION_MAJOR@0.cgi

The location where the source has been placed will be further referred as
${tomcat.source}.

The Tomcat local build process does not modify line-endings. The svn repository
is configured so that all files will be checked out with the line-ending
appropriate for the current platform. When using a source package you should
ensure that you use the source package that has the appropriate line-ending
for your platform:

  zip    -> CRLF
  tar.gz -> LF

Note that the release build process does modify line-endings to ensure that
each release package has the appropriate line-endings.

(3.2) Building

 1. The build is controlled by creating a ${tomcat.source}/build.properties
    file.

    It is recommended to always create the file, because of unfortunate
    default value of base.path property. You may start with the following
    content for the file:

        # ----- Default Base Path for Dependent Packages -----
        # Replace this path with the directory path where dependencies binaries
        # should be downloaded
        base.path=/home/me/some-place-to-download-to

 2. Configure base.path property by adding it to the
    ${tomcat.source}/build.properties file.

    The base.path property specifies the place where Tomcat dependencies
    required by the build are downloaded. It is recommended to place this
    directory outside of the source tree, so that you do not waste your
    time re-downloading the libraries.

* NOTE: The default value of the base.path property configures the build script
  to download the libraries required to build Tomcat to the
  ${user.home}/tomcat-build-libs directory.

* NOTE: Users accessing the Internet through a proxy must use the properties
  file to indicate to Ant the proxy configuration.

  The following properties should be added to the ${tomcat.source}/build.properties
  file.

        proxy.use=true
        proxy.host=proxy.domain
        proxy.port=8080
        proxy.user=username
        proxy.password=password

  See Apache Ant documentation for the <setproxy> task for details.

 3. Go to the sources directory and run Ant:

        cd ${tomcat.source}
        ant

    This will execute the "deploy" target in build.xml.

    Once the build has completed successfully, a usable Tomcat installation
    will have been produced in the ${tomcat.source}/output/build directory,
    and can be started and stopped with the usual scripts.

    Note that the build includes Tomcat documentation, which can be found
    in the output/build/webapps/docs directory.

    The path of the output directory can be controlled by specifying the
    "tomcat.output" property in the build.properties file.

* NOTE: Do not run the build as the root user. Building and running Tomcat
  does not require root privileges.


(4) Updating sources and rebuilding

It is recommended that you regularly update the downloaded Tomcat @VERSION_MAJOR_MINOR@
sources using your git client.

For a quick rebuild of only modified code you can use:

    cd ${tomcat.source}
    ant


(5) Special builds

There are several targets in Tomcat build files that are useful to be
called separately. They build components that you may want to build
quickly, or ones that are included in the full release and are not built
during the default "deploy" build.

(5.1) Building documentation

The documentation web application is built during the default "deploy"
build.

It can be built quickly by using the following commands:

    cd ${tomcat.source}
    ant build-docs

The output of this command will be found in the following directory:

    output/build/webapps/docs


The API documentation (Javadoc) is built during a "release" build. It is
easy to build it separately by using the following commands:

    cd ${tomcat.source}
    ant javadoc

The output of this command will be found in the following directories:

    output/dist/webapps/docs/api
    output/dist/webapps/docs/elapi
    output/dist/webapps/docs/jspapi
    output/dist/webapps/docs/servletapi


(5.2) Building the extras (commons-logging, webservices etc.)

These components are documented on the "Additional Components"
(extras.html) page of documentation. They are built during a "release"
build.

You can build them by using the following commands:

    cd ${tomcat.source}
    ant extras

(5.3) Building the embedded packages

These are built during a "release" build.

You can build them by using the following commands:

    cd ${tomcat.source}
    ant embed


(6) Building a full release (as provided via the ASF download pages)

    A full release includes the Windows installer which requires a Windows
    environment to be available to create it. If not building in a Windows
    environment, the build scripts assume that Wine is available. If this is not
    the case, the skip.installer property may be set to skip the creation of the
    Windows installer.

    Provided that Wine is available on non-Windows platforms, a full release
    build may be made on Windows, Linux or MacOS.

 1. Configure GPG, if needed

    If the released artifacts have to be cryptographically signed with a
    PGP signature, like the official ASF releases are, the following
    property can be added to the build.properties file:

        # Location of GPG executable (used only for releases)
        gpg.exec=/path/to/gpg

    You do not need it if you do not plan to sign the release.

    If "gpg.exec" property does not point to an existing file, it will be
    ignored and this feature will be disabled.

    You will be prompted for the GPG passphrase when the release build
    starts, unless "gpg.passphrase" property is set.

 2. If building the Windows installer

    If running the build in a UAC enabled environment, building the Windows
    installer requires elevated privileges. The simplest way to do this is to
    open the command prompt used for the build with the "Run as administrator"
    option.

 3. Configure the code signing service

    ASF committers performing official releases will need to configure the code
    signing service so that the Windows installer is signed during the build
    process. The following properties need to be added to the build.properties
    file:

        # Location of GPG executable (used only for releases)
        gpg.exec=/path/to/gpg
        # Code signing of Windows installer
        do.codesigning=true
        codesigning.storepass=request-via-pmc

    Release managers will be provided with the necessary credentials by the PMC.

 4. Build the release:

    cd ${tomcat.source}
    ant release


(7) Tests

(7.1) Running Tomcat tests

Tomcat includes a number of junit tests. The tests are not run when a
release is built. There is separate command to run them.

To run the testsuite use the following command:

    cd ${tomcat.source}
    ant test

It is advisable to redirect output of the above command to a file for later
inspection.

The JUnit reports generated by the tests will be written to the following
directory:

    output/build/logs

By default the testsuite is run three times to test 3 different
implementations of Tomcat connectors: NIO, NIO2 and APR. (If you are not
familiar with Tomcat connectors, see config/http.html in documentation for
details).

The 3 runs are enabled and disabled individually by the following
properties, which all are "true" by default:

    execute.test.nio=true
    execute.test.nio2=true
    execute.test.apr=true

The APR connector can be tested only if Tomcat-Native library binaries are
found by the testsuite. The "test.apr.loc" property specifies the directory
where the library binaries are located.

By default the "test.apr.loc" property specifies the following location:

    output/build/bin/native/

If you are on Windows and want to test the APR connector you can put the
tcnative-1.dll file into ${tomcat.source}/bin/native/ and it will be copied
into the above directory when the build runs.

The unit tests include tests of the clustering functionality which require
multicast to be enabled. There is a simple application provided in the Tomcat
test source (org.apache.catalina.tribes.TesterMulticast) that can be used to
check if a machine supports multicast. Notes on enabling multicast for different
operating systems are provided in the Javadoc for that class.


(7.2) Running a single test

It is possible to run a single JUnit test class by adding the "test.entry"
property to the build.properties file. The property specifies the name of
the test class.

For example:

    test.entry=org.apache.catalina.util.TestServerInfo

It is possible to further limit such run to a number of selected test
methods by adding "test.entry.methods" property. The property specifies a
comma-separated list of test case methods.

For example:

    test.entry=org.apache.el.lang.TestELArithmetic
    test.entry.methods=testMultiply01,testMultiply02


(7.3) Running a set of tests

It is possible to run a set of JUnit test classes by adding the "test.name"
property to the build.properties file. The property specifies an Ant
includes pattern for the fileset of test class files to run.

The default value is "**/Test*.java", so all test classes are being
executed (with few exceptions - see build.xml for several exclude patterns).

You can include multiple patterns by concatenating them with a comma (",")
as the separator.

For example:

    test.name=**/TestSsl.java,**/TestWebSocketFrameClientSSL.java

You can exclude specific JUnit test classes by adding the "test.exclude"
property to the build.properties file. The property specifies an Ant
excludes pattern for the fileset of test class files to exclude form the run.
The default value is empty, so no classes are excluded. The syntax is the same
as for the property "test.name".


(7.4) Other configuration options

 1. It is possible to configure the directory where JUnit reports are
 written to. It is configured by "test.reports" property. The default
 value is

        output/build/logs

 2. It is possible to enable generation of access log file when the tests
 are run. This is off by default and can be enabled by the following
 property:

        test.accesslog=true

 The "access_log.<date>" file will be written to the same directory as
 JUnit reports,

        output/build/logs

 3. The testsuite respects logging configuration as configured by
 ${tomcat.source}/conf/logging.properties

 The log files will be written to the temporary directory used by the
 tests,

        output/test-tmp/logs

 4. It is possible to configure formatter used by JUnit reports.
 Configuration properties are "junit.formatter.type",
 "junit.formatter.extension" and "junit.formatter.usefile".

 For example the following property disables generation of separate report
 files:

        junit.formatter.usefile=false

 5. It is possible to speed up testing by letting JUnit to run several
 tests in parallel.

 This is configured by setting "test.threads" property. The recommended
 value is one thread per core.

 6. Optional support is provided for the Cobertura code coverage tool.

NOTE: Cobertura is licensed under GPL v2 with parts of it being under
      Apache License v1.1. See https://cobertura.github.io/cobertura/ for details.
      Using it during Tomcat build is optional and is off by default.

 Cobertura can be enabled using the following properties:

        test.cobertura=true
        test.threads=1

 Using Cobertura currently requires setting test.threads configuration
 property to the value of 1. Setting that property to a different value
 will disable code coverage.

 The report files by default are written to

        output/coverage

 7. The performance tests are written to run reasonably powerful machines (such
    as a developer may use day to day) assuming no other resource hungry
    processes are running.

    These assumptions are not always true (e.g. on CI systems running in a
    virtual machine) so the performance tests may be disabled by using the
    following property:

        test.excludePerformance=true

 8. Some tests include checks that the access log valve entries are as expected.
    These checks include timings. On slower / loaded systems these checks will
    often fail. The checks may be relaxed by using the following property:

        test.relaxTiming=true

 9. It is known that some platforms (e.g. OSX El Capitan) require IPv4 to
    be the default for the multicast tests to work. This is configured by
    the following property:

        java.net.preferIPv4Stack=true

 10. By default the output of unit tests is sent to the console and can be
     quite verbose. The output can be disabled by setting the property:

        test.verbose=false

(8) Source code checks

(8.1) Checkstyle

NOTE: Checkstyle is licensed under LGPL. Using Checkstyle during Tomcat
      build is optional and is off by default.

      See http://checkstyle.sourceforge.net/ for more information.

Tomcat comes with a Checkstyle configuration that tests its source code
for certain conventions, like presence of the license header.

To enable Checkstyle, add the following property to build.properties file:

    execute.validate=true

Once Checkstyle is enabled, the check will be performed automatically
during the build. The check is run before compilation of the source code.

To speed-up repeated runs of this check, a cache is configured. The cache
is located in the following directory:

    output/res/checkstyle

It is possible to run the check separately by calling the "validate"
target. The command is:

    cd ${tomcat.source}
    ant -Dexecute.validate=true validate


(8.2) FindBugs

NOTE: FindBugs is licensed under LGPL. Using Findbugs during Tomcat build is
      optional and is off by default.

      See https://spotbugs.github.io/ for more information.

To enable FindBugs, add the following property to build.properties file:

    execute.findbugs=true

To compile Tomcat classes and generate a FindBugs report, call the
"findbugs" target. For example:

    cd ${tomcat.source}
    ant -Dexecute.findbugs=true findbugs

The report file by default is written to

    output/findbugs


(8.3) End-of-line conventions check

You usually would not need to run this check. You can skip this section.

Apache Tomcat project has convention that all of its textual source files,
stored in the Git repository, use Unix style LF line endings.

This test is used by developers to check that the source code adheres to
this convention. It verifies that the ends of lines in textual files are
appropriate. The idea is to run this check regularly and notify developers
when an inconsistency is detected.

The command to run this test is:

    cd ${tomcat.source}
    ant validate-eoln