"Unknown extension point" in plugin.xml problem - eclipse

Question

In "Contributing to Eclipse" book it is written that to introduce an extension point you should type the next section in plugin.xml
<extension point="org.eclipse.contribution.junit.listeners">
<listener
class="org.eclipse.contribution.junit.RunTestAction$Listener">
</listener>
</extension>
But this code gives me the "Unknown extension point" error".

Answer 1

Read the book carefully, extension point is defined in the same plugin.xml as <extension-point id="listeners" name="Test Listeners"/>
Get sample code from Downloads at http://www.informit.com/store/product.aspx?isbn=0321205758
<?xml version="1.0" encoding="UTF-8"?>
<plugin
id="org.eclipse.contribution.junit"
name="JUnit Plug-in"
version="1.0.0"
provider-name=""
class="org.eclipse.contribution.junit.JUnitPlugin">
<runtime>
<library name="contribjunit.jar">
<export name = "*"/>
</library>
</runtime>
<requires>
<import plugin="org.eclipse.core.resources"/>
<import plugin="org.eclipse.ui"/>
<import plugin="org.eclipse.jdt.core"/>
<import plugin="org.junit"/>
<import plugin="org.eclipse.debug.core"/>
<import plugin="org.eclipse.jdt.launching"/>
</requires>
<extension-point id="listeners" name="Test Listeners"/>
<extension point="org.eclipse.ui.popupMenus">
<objectContribution
objectClass="org.eclipse.jdt.core.IType"
id="org.eclipse.contribution.junit.runtest">
<action
label="Run Test"
class="org.eclipse.contribution.junit.RunTestAction"
enablesFor="1"
id="org.eclipse.contribution.junit.runtest.action">
</action>
</objectContribution>
</extension>
<extension point="org.eclipse.contribution.junit.listeners">
<listener
class="org.eclipse.contribution.junit.RunTestAction$Listener">
</listener>
</extension>
</plugin>
Cheers,
Max