Trying to do the contact example, and trying to debug the application I get the following error:

F:\NetBeans\formacion\learnEAuno\nbproject\build-impl.xml:313: The following error occurred while executing this line:
F:\NetBeans\formacion\learnEAuno\nbproject\build-impl.xml:326: java.net.MalformedURLException: no protocol: 
${client.url}

The problem is that I don't have any idea of what is happening, because it looks as if the system is going something 
wrong.
The GlassFish V2 is started in debug mode.

 The two errors refers to this code of the build-impl.xml file:
 <target depends="dist" description="Debug project in IDE." if="netbeans.home" name="run-debug" unless="app.client">
        <nbdeploy clientModuleUri="${client.module.uri}" clientUrlPart="${client.urlPart}" debugmode="true"/>
        <antcall target="connect-debugger"/>
        <antcall target="debug-display-browser"/>
    </target>
more precisely the debug-display-browser symbol.
The other line refers to
    <target if="do.display.browser" name="debug-display-browser">
        <nbbrowse url="${client.url}"/>
    </target>

The complete log is:
pre-init:
init-private:
init-userdir:
init-user:
init-project:
do-init:
post-init:
init-check:
init:
deps-jar:
deps-j2ee-archive:
init:
init:
deps-jar:
compile:
library-inclusion-in-manifest:
dist-ear:
deps-jar:
compile:
library-inclusion-in-manifest:
dist-ear:
init:
deps-jar:
compile:
library-inclusion-in-manifest:
dist-ear:
init:
deps-module-jar:
deps-ear-jar:
init:
deps-jar:
compile:
library-inclusion-in-manifest:
dist-ear:
deps-jar:
library-inclusion-in-archive:
library-inclusion-in-manifest:
compile:
compile-jsps:
do-ear-dist:
dist-ear:
pre-pre-compile:
pre-compile:
do-compile:
post-compile:
compile:
pre-dist:
do-dist-without-manifest:
do-dist-with-manifest:
Building jar: F:\NetBeans\formacion\learnEAuno\dist\learnEAuno.ear
post-dist:
dist:
run-debug:
Incrementally deploying learnEAuno_localhost:4848_server
Completed incremental distribution of learnEAuno
connect-debugger:
Non-existing path "F:\NetBeans\formacion\learnEAuno\${javac.classpath}" provided.
Non-existing path "F:\NetBeans\formacion\learnEAuno\${run.classpath}" provided.
Attached JPDA debugger to localhost:9009
debug-display-browser:
Browsing: ${client.url}
F:\NetBeans\formacion\learnEAuno\nbproject\build-impl.xml:313: The following error occurred while executing this line:
F:\NetBeans\formacion\learnEAuno\nbproject\build-impl.xml:326: java.net.MalformedURLException: no protocol: 
${client.url}
----------------------------------------------
The complete build-impl.xml file is

<?xml version="1.0" encoding="UTF-8"?>
<!--
*** GENERATED FROM project.xml - DO NOT EDIT  ***
***         EDIT ../build.xml INSTEAD         ***

For the purpose of easier reading the script
is divided into following sections:

  - initialization
  - compilation
  - dist
  - execution
  - debugging
  - cleanup

-->
<project xmlns:ear2="http://www.netbeans.org/ns/j2ee-earproject/2" basedir=".." default="default" name="learnEAuno-
impl">
    <import file="ant-deploy.xml"/>
    <target depends="dist" description="Build whole project." name="default"/>
    <!-- 
    INITIALIZATION SECTION 
    -->
    <target name="pre-init">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="pre-init" name="init-private">
        <property file="nbproject/private/private.properties"/>
    </target>
    <target depends="pre-init,init-private" name="init-userdir">
        <property location="${netbeans.user}/build.properties" name="user.properties.file"/>
    </target>
    <target depends="pre-init,init-private,init-userdir" name="init-user">
        <property file="${user.properties.file}"/>
    </target>
    <target depends="pre-init,init-private,init-userdir,init-user" name="init-project">
        <property file="nbproject/project.properties"/>
    </target>
    <target depends="pre-init,init-private,init-userdir,init-user,init-project" name="do-init">
        <!-- The two properties below are usually overridden -->
        <!-- by the active platform. Just a fallback. -->
        <property name="default.javac.source" value="1.4"/>
        <property name="default.javac.target" value="1.4"/>
        <condition property="do.compile.jsps">
            <istrue value="${compile.jsps}"/>
        </condition>
        <condition property="do.display.browser">
            <and>
                <istrue value="${display.browser}"/>
                <isset property="client.module.uri"/>
                <not>
                    <isset property="app.client"/>
                </not>
            </and>
        </condition>
        <available file="${meta.inf}/MANIFEST.MF" property="has.custom.manifest"/>
        <condition else="" property="j2ee.appclient.mainclass.tool.param" value="-mainclass ${main.class}">
            <and>
                <isset property="main.class"/>
                <not>
                    <equals arg1="${main.class}" arg2="" trim="true"/>
                </not>
            </and>
        </condition>
        <condition else="" property="j2ee.appclient.jvmoptions.param" value="${j2ee.appclient.jvmoptions}">
            <and>
                <isset property="j2ee.appclient.jvmoptions"/>
                <not>
                    <equals arg1="${j2ee.appclient.jvmoptions}" arg2="" trim="true"/>
                </not>
            </and>
        </condition>
        <condition else="" property="application.args.param" value="${application.args}">
            <and>
                <isset property="application.args"/>
                <not>
                    <equals arg1="${application.args}" arg2="" trim="true"/>
                </not>
            </and>
        </condition>
        <condition property="can.debug.appclient">
            <and>
                <isset property="netbeans.home"/>
                <isset property="app.client"/>
            </and>
        </condition>
    </target>
    <target name="post-init">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="pre-init,init-private,init-userdir,init-user,init-project,do-init" name="init-check">
        <fail unless="build.dir">Must set build.dir</fail>
        <fail unless="build.generated.dir">Must set build.generated.dir</fail>
        <fail unless="dist.dir">Must set dist.dir</fail>
        <fail unless="build.classes.excludes">Must set build.classes.excludes</fail>
        <fail unless="dist.jar">Must set dist.jar</fail>
    </target>
    <target depends="pre-init,init-private,init-userdir,init-user,init-project,do-init,post-init,init-check" 
name="init"/>
    <!--
    COMPILATION SECTION
    -->
    <target depends="init" name="deps-jar" unless="no.deps"/>
    <target depends="init" name="deps-j2ee-archive" unless="no.deps">
        <ant antfile="${project.learnEAuno-app-client}/build.xml" inheritall="false" target="dist-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
        <ant antfile="${project.learnEAuno-ejb}/build.xml" inheritall="false" target="dist-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
        <ant antfile="${project.learnEAuno-war}/build.xml" inheritall="false" target="dist-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
    </target>
    <target depends="init,deps-jar,deps-j2ee-archive" name="pre-pre-compile"/>
    <target name="pre-compile">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="init,deps-jar,pre-pre-compile,pre-compile" name="do-compile">
        <copy todir="${build.dir}/META-INF">
            <fileset dir="${meta.inf}"/>
        </copy>
        <copy file="${reference.learnEAuno-war.dist-ear}" todir="${build.dir}//"/>
        <copy file="${reference.learnEAuno-app-client.j2ee-module-car}" todir="${build.dir}//"/>
        <copy file="${reference.learnEAuno-ejb.dist-ear}" todir="${build.dir}//"/>
    </target>
    <target name="post-compile">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="init,deps-jar,pre-pre-compile,pre-compile,do-compile,post-compile" description="Compile project." 
name="compile"/>
    <!--
    DIST BUILDING SECTION
    -->
    <target name="pre-dist">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="init,compile,pre-dist" name="do-dist-without-manifest" unless="has.custom.manifest">
        <dirname file="${dist.jar}" property="dist.jar.dir"/>
        <mkdir dir="${dist.jar.dir}"/>
        <jar compress="${jar.compress}" jarfile="${dist.jar}">
            <fileset dir="${build.dir}"/>
        </jar>
    </target>
    <target depends="init,compile,pre-dist" if="has.custom.manifest" name="do-dist-with-manifest">
        <dirname file="${dist.jar}" property="dist.jar.dir"/>
        <mkdir dir="${dist.jar.dir}"/>
        <jar compress="${jar.compress}" jarfile="${dist.jar}" manifest="${meta.inf}/MANIFEST.MF">
            <fileset dir="${build.dir}"/>
        </jar>
    </target>
    <target name="post-dist">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="init,compile,pre-dist,do-dist-without-manifest,do-dist-with-manifest,post-dist" 
description="Build distribution (JAR)." name="dist"/>
    <!--
    EXECUTION SECTION
    -->
    <target depends="run-deploy,run-display-browser,run-ac" description="Deploy to server." name="run"/>
    <target name="pre-run-deploy">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target name="post-run-deploy">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target name="-pre-nbmodule-run-deploy">
        <!-- Empty placeholder for easier customization. -->
        <!-- This target can be overriden by NetBeans modules. Don't override it directly, use -pre-run-deploy task 
instead. -->
    </target>
    <target name="-post-nbmodule-run-deploy">
        <!-- Empty placeholder for easier customization. -->
        <!-- This target can be overriden by NetBeans modules. Don't override it directly, use -post-run-deploy task 
instead. -->
    </target>
    <target name="-run-deploy-am" unless="no.deps">
        <!-- Task to deploy to the Access Manager runtime. -->
        <ant antfile="${project.learnEAuno-app-client}/build.xml" inheritall="false" target="-run-deploy-am"/>
        <ant antfile="${project.learnEAuno-ejb}/build.xml" inheritall="false" target="-run-deploy-am"/>
        <ant antfile="${project.learnEAuno-war}/build.xml" inheritall="false" target="-run-deploy-am"/>
    </target>
    <target depends="dist,pre-run-deploy,-pre-nbmodule-run-deploy,-run-deploy-nb,-init-deploy-ant,-deploy-ant,-run-
deploy-am,-post-nbmodule-run-deploy,post-run-deploy" name="run-deploy"/>
    <target if="netbeans.home" name="-run-deploy-nb">
        <nbdeploy clientModuleUri="${client.module.uri}" clientUrlPart="${client.urlPart}" debugmode="false" 
forceRedeploy="${forceRedeploy}"/>
    </target>
    <target name="-init-deploy-ant" unless="netbeans.home">
        <property name="deploy.ant.archive" value="${dist.jar}"/>
        <property name="deploy.ant.resource.dir" value="${resource.dir}"/>
        <property name="deploy.ant.enabled" value="true"/>
    </target>
    <target depends="dist,-run-undeploy-nb,-init-deploy-ant,-undeploy-ant" name="run-undeploy"/>
    <target if="netbeans.home" name="-run-undeploy-nb">
        <fail message="Undeploy is not supported from within the IDE"/>
    </target>
    <target depends="dist" name="verify">
        <nbverify file="${dist.jar}"/>
    </target>
    <target depends="run-deploy,-init-display-browser,-display-browser-nb,-display-browser-cl" name="run-display-
browser"/>
    <target if="do.display.browser" name="-init-display-browser">
        <condition property="do.display.browser.nb">
            <isset property="netbeans.home"/>
        </condition>
        <condition property="do.display.browser.cl">
            <and>
                <isset property="deploy.ant.enabled"/>
                <isset property="deploy.ant.client.url"/>
            </and>
        </condition>
    </target>
    <target if="do.display.browser.nb" name="-display-browser-nb">
        <nbbrowse url="${client.url}"/>
    </target>
    <target if="do.display.browser.cl" name="-get-browser" unless="browser">
        <condition property="browser" value="rundll32">
            <os family="windows"/>
        </condition>
        <condition else="" property="browser.args" value="url.dll,FileProtocolHandler">
            <os family="windows"/>
        </condition>
        <condition property="browser" value="/usr/bin/open">
            <os family="mac"/>
        </condition>
        <property environment="env"/>
        <condition property="browser" value="${env.BROWSER}">
            <isset property="env.BROWSER"/>
        </condition>
        <condition property="browser" value="/usr/bin/firefox">
            <available file="/usr/bin/firefox"/>
        </condition>
        <condition property="browser" value="/usr/local/firefox/firefox">
            <available file="/usr/local/firefox/firefox"/>
        </condition>
        <condition property="browser" value="/usr/bin/mozilla">
            <available file="/usr/bin/mozilla"/>
        </condition>
        <condition property="browser" value="/usr/local/mozilla/mozilla">
            <available file="/usr/local/mozilla/mozilla"/>
        </condition>
        <condition property="browser" value="/usr/sfw/lib/firefox/firefox">
            <available file="/usr/sfw/lib/firefox/firefox"/>
        </condition>
        <condition property="browser" value="/opt/csw/bin/firefox">
            <available file="/opt/csw/bin/firefox"/>
        </condition>
        <condition property="browser" value="/usr/sfw/lib/mozilla/mozilla">
            <available file="/usr/sfw/lib/mozilla/mozilla"/>
        </condition>
        <condition property="browser" value="/opt/csw/bin/mozilla">
            <available file="/opt/csw/bin/mozilla"/>
        </condition>
    </target>
    <target depends="-get-browser" if="do.display.browser.cl" name="-display-browser-cl">
        <fail unless="browser">
            Browser not found, cannot launch the deployed application. Try to set the BROWSER environment variable.
        </fail>
        <property name="browse.url" value="${deploy.ant.client.url}${client.urlPart}"/>
        <echo>Launching ${browse.url}</echo>
        <exec executable="${browser}" spawn="true">
            <arg line="${browser.args} ${browse.url}"/>
        </exec>
    </target>
    <target depends="init" if="app.client" name="run-ac">
        <antcall target="run-${app.client}"/>
    </target>
    <target depends="-tool-learnEAuno-app-client,-java-learnEAuno-app-client" name="run-learnEAuno-app-client"/>
    <target depends="-as-retrieve-option-workaround" if="j2ee.appclient.mainclass.args" name="-tool-learnEAuno-app-
client" unless="j2ee.clientName">
        <java classname="${j2ee.appclient.tool.mainclass}" fork="true">
            <jvmarg line="${j2ee.appclient.tool.jvmoptions}"/>
            <jvmarg line="${j2ee.appclient.jvmoptions.param}"/>
            <arg line="${j2ee.appclient.tool.args}"/>
            <arg line="-client ${client.jar}"/>
            <arg line="${j2ee.appclient.mainclass.tool.param}"/>
            <arg line="${application.args.param}"/>
            <classpath>
                <path path="${j2ee.platform.classpath}:${j2ee.appclient.tool.runtime}"/>
            </classpath>
            <syspropertyset>
                <propertyref prefix="run-sys-prop."/>
                <mapper from="run-sys-prop.*" to="*" type="glob"/>
            </syspropertyset>
        </java>
    </target>
    <target if="j2ee.clientName" name="-java-learnEAuno-app-client" unless="j2ee.appclient.mainclass.args">
        <java classname="${main.class}" fork="true">
            <jvmarg line="${j2ee.appclient.tool.jvmoptions}"/>
            <jvmarg line="-Dj2ee.clientName=${app.client}"/>
            <jvmarg line="${j2ee.appclient.jvmoptions.param}"/>
            <arg line="${application.args.param}"/>
            <classpath>
                <path path="${jar.content.additional}:${j2ee.platform.classpath}:${j2ee.appclient.tool.runtime}"/>
            </classpath>
            <syspropertyset>
                <propertyref prefix="run-sys-prop."/>
                <mapper from="run-sys-prop.*" to="*" type="glob"/>
            </syspropertyset>
        </java>
    </target>
    <target if="j2ee.appclient.mainclass.args" name="-as-retrieve-option-workaround" unless="j2ee.clientName">
        <property name="client.jar" value="${dist.dir}/learnEAunoClient.jar"/>
        <sleep seconds="3"/>
        <copy file="${wa.copy.client.jar.from}/learnEAuno/learnEAunoClient.jar" todir="${dist.dir}"/>
    </target>
    <!--
    DEBUGGING SECTION
    -->
    <target depends="run-debug,run-debug-appclient" description="Deploy to server." name="debug"/>
    <target depends="dist" description="Debug project in IDE." if="netbeans.home" name="run-debug" unless="app.client">
        <nbdeploy clientModuleUri="${client.module.uri}" clientUrlPart="${client.urlPart}" debugmode="true"/>
        <antcall target="connect-debugger"/>
        <antcall target="debug-display-browser"/>
    </target>
    <target name="connect-debugger" unless="is.debugged">
        <nbjpdaconnect address="${jpda.address}" host="${jpda.host}" name="${name}" transport="${jpda.transport}">
            <classpath>
                <path path="${debug.classpath}"/>
            </classpath>
            <sourcepath>
                <path path="${ear.docbase.dirs}"/>
            </sourcepath>
        </nbjpdaconnect>
    </target>
    <target if="do.display.browser" name="debug-display-browser">
        <nbbrowse url="${client.url}"/>
    </target>
    <target name="-init-debug-args">
        <property name="version-output" value="java version &quot;${ant.java.version}"/>
        <condition property="have-jdk-older-than-1.4">
            <or>
                <contains string="${version-output}" substring="java version &quot;1.0"/>
                <contains string="${version-output}" substring="java version &quot;1.1"/>
                <contains string="${version-output}" substring="java version &quot;1.2"/>
                <contains string="${version-output}" substring="java version &quot;1.3"/>
            </or>
        </condition>
        <condition else="-Xdebug" property="debug-args-line" value="-Xdebug -Xnoagent -Djava.compiler=none">
            <istrue value="${have-jdk-older-than-1.4}"/>
        </condition>
    </target>
    <target depends="init,-init-debug-args" if="can.debug.appclient" name="run-debug-appclient">
        <macrodef name="debug-appclient" uri="http://www.netbeans.org/ns/j2ee-earproject/2">
            <attribute name="mainclass"/>
            <attribute default="${debug.classpath}" name="classpath"/>
            <element name="customize" optional="true"/>
            <attribute default="${application.args.param}" name="args"/>
            <sequential>
                <parallel>
                    <java classname="@{mainclass}" fork="true">
                        <jvmarg line="${j2ee.appclient.tool.jvmoptions}"/>
                        <jvmarg line="${debug-args-line}"/>
                        <jvmarg value="-
Xrunjdwp:transport=${jpda.transport},server=y,address=${jpda.address},suspend=y"/>
                        <jvmarg line="${j2ee.appclient.jvmoptions.param}"/>
                        <arg line="@{args}"/>
                        <classpath>
                            <path path="${j2ee.platform.classpath}:${j2ee.appclient.tool.runtime}"/>
                            <path path="@{classpath}"/>
                        </classpath>
                        <syspropertyset>
                            <propertyref prefix="run-sys-prop."/>
                            <mapper from="run-sys-prop.*" to="*" type="glob"/>
                        </syspropertyset>
                        <customize/>
                    </java>
                    <nbjpdaconnect address="${jpda.address}" host="${jpda.host}" name="${name}" 
transport="${jpda.transport}">
                        <classpath>
                            <path path="${j2ee.platform.classpath}:${j2ee.appclient.tool.runtime}"/>
                            <path path="@{classpath}"/>
                        </classpath>
                        <sourcepath>
                            <path path="${src.dir}"/>
                        </sourcepath>
                    </nbjpdaconnect>
                </parallel>
            </sequential>
        </macrodef>
        <nbdeploy clientModuleUri="${client.module.uri}" clientUrlPart="${client.urlPart}" debugmode="false"/>
        <antcall target="debug-${app.client}"/>
    </target>
    <target depends="-debug-tool-learnEAuno-app-client,-debug-java-learnEAuno-app-client" name="debug-learnEAuno-app-
client"/>
    <target depends="init,-as-retrieve-option-workaround" if="j2ee.appclient.mainclass.args" name="-debug-tool-
learnEAuno-app-client" unless="j2ee.clientName">
        <ear2:debug-appclient args="-client ${client.jar} ${j2ee.appclient.tool.args} 
${j2ee.appclient.mainclass.tool.param} ${application.args.param}" mainclass="${j2ee.appclient.tool.mainclass}"/>
    </target>
    <target if="j2ee.clientName" name="-debug-java-learnEAuno-app-client" unless="j2ee.appclient.mainclass.args">
        <ear2:debug-appclient args="${application.args.param}" classpath="${jar.content.additional}" 
mainclass="${main.class}"/>
    </target>
    <!--
    CLEANUP SECTION
    -->
    <target depends="init" name="deps-clean" unless="no.deps">
        <ant antfile="${project.learnEAuno-app-client}/build.xml" inheritall="false" target="clean-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
        <ant antfile="${project.learnEAuno-ejb}/build.xml" inheritall="false" target="clean-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
        <ant antfile="${project.learnEAuno-war}/build.xml" inheritall="false" target="clean-ear">
            <property location="${build.dir}" name="dist.ear.dir"/>
        </ant>
    </target>
    <target depends="init" name="do-clean">
        <delete dir="${build.dir}"/>
        <delete dir="${dist.dir}"/>
        <delete dir="${build.dir}"/>
    </target>
    <target name="post-clean">
        <!-- Empty placeholder for easier customization. -->
        <!-- You can override this target in the ../build.xml file. -->
    </target>
    <target depends="init,deps-clean,do-clean,post-clean" description="Clean build products." name="clean"/>
</project>