How can I exctract a revision number from XML in bash?

<?xml version='1.0' encoding='UTF-8'?>
<build>
<actions>
<hudson.model.CauseAction>
  <causes>
    <hudson.model.Cause_-UserCause>
      <authenticationName>roman</authenticationName>
    </hudson.model.Cause_-UserCause>
  </causes>开发者_JS百科;
</hudson.model.CauseAction>
<hudson.scm.SubversionTagAction>
  <build class="build" reference="../../.."/>
  <tags class="hudson.util.CopyOnWriteMap$Tree">
    <no-comparator/>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>http://svn.exoplatform.org/projects/jcr-benchmark/trunk</url>
        <revision>70141</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/core/trunk</url>
        <revision>4679</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/dev-resources/tags/1.2.0</url>
        <revision>75</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/docs-style/tags/1</url>
        <revision>2031</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk</url>
        <revision>4687</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/junit.framework/tags/1.2.1-GA</url>
        <revision>1961</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://anonsvn.jboss.org/repos/exo-jcr/kernel/trunk</url>
        <revision>4673</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://*****.*****.org/repos/****/parent/tags/9</url>
        <revision>4503</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
    <entry>
      <hudson.scm.SubversionSCM_-SvnInfo>
        <url>https://*****.*****.org/repos/****/parent/tags/9</url>
        <revision>4675</revision>
      </hudson.scm.SubversionSCM_-SvnInfo>
      <list/>
    </entry>
  </tags>
</hudson.scm.SubversionTagAction>
<hudson.scm.SVNRevisionState>
  <revisions>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/docs-style/tags/1</string>
      <long>2031</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/dev-resources/tags/1.2.0</string>
      <long>75</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk</string>
      <long>4687</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/ws/trunk</string>
      <long>4675</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/kernel/trunk</string>
      <long>4673</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/junit.framework/tags/1.2.1-GA</string>
      <long>1961</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/core/trunk</string>
      <long>4679</long>
    </entry>
    <entry>
      <string>https://anonsvn.jboss.org/repos/exo-jcr/parent/tags/9</string>
      <long>4503</long>
    </entry>
    <entry>
      <string>http://svn.exoplatform.org/projects/jcr-benchmark/trunk</string>
      <long>70141</long>
    </entry>
  </revisions>
</hudson.scm.SVNRevisionState>
<hudson.plugins.chucknorris.RoundhouseAction>
  <mStyle>THUMB_UP</mStyle>
  <mFact>Chuck Norris can spawn threads that complete before they are started.</mFact>
</hudson.plugins.chucknorris.RoundhouseAction>
<htmlpublisher.HtmlPublisherTarget_-HTMLBuildAction>
  <actualHtmlPublisherTarget>
    <reportName>Japex Reports</reportName>
    <reportDir>TestingResults/</reportDir>
    <reportFiles>index.html</reportFiles>
    <keepAll>true</keepAll>
    <wrapperName>htmlpublisher-wrapper.html</wrapperName>
  </actualHtmlPublisherTarget>
  <outer-class reference="../actualHtmlPublisherTarget"/>
  <build class="build" reference="../../.."/>
  <outer-class defined-in="htmlpublisher.HtmlPublisherTarget$HTMLBuildAction" reference="../actualHtmlPublisherTarget"/>
        </htmlpublisher.HtmlPublisherTarget_-HTMLBuildAction>
    </actions>
    <number>38</number>
    <result>SUCCESS</result>
    <duration>286787</duration>
    <charset>UTF-8</charset>
    <keepLog>false</keepLog>
    <builtOn></builtOn>
    <workspace>/home/roman/.hudson/jobs/Express-Testing-JCR-Trunk/workspace</workspace>
    <hudsonVersion>1.417</hudsonVersion>
    <scm class="hudson.scm.SubversionChangeLogParser"/>
    <culprits/>
</build>

I need get revision (4687) from <entry> <string>https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk</string> <long>4687</long> </entry>

The xgrep or xpath utilities can help you with this:

xgrep -x '/build/actions/hudson.scm.SubversionTagAction/tags/entry/hudson.scm.SubversionSCM_-SvnInfo[url="https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk"]/revision/text()' sample.xml 

or:

xpath -q -e '/build/actions/hudson.scm.SubversionTagAction/tags/entry/hudson.scm.SubversionSCM_-SvnInfo[url="https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk"]/revision/text()' sample.xml

Always use an XML parser when dealing with XML content. If you don't you might encounter strange problems, as this classical answer illustrates: RegEx match open tags except XHTML self-contained tags

If the url never change and that <revision> always come after it then you can use the following:

$ grep -A 1 '<url>https://anonsvn.jboss.org/repos/exo-jcr/jcr/trunk' test.xhtml |
      tail -1 |
      sed -e 's/[^0-9]//g'