Problem with Ant

[Kamil]

Hello,

I am trying to run simple EchoClient program on my linux machine that
connects to the port 7 of the host. It works perfectly from the
command line. However when I try to run it from Ant I get
NullPointerException. It seems that Ant has control over input and
output stream. Question is: Is there any way that Ant can hand over
the control over streams to the program that is currently running?

Here are the files I am using

build.xml
<?xml version="1.0" encoding="UTF-8"?>
<project name="MyProject" default="run-client" basedir=".">
<description>
This is my main build.xml file
</description>
<property name="classes" value="${basedir}/classes"/>
<property name="data" value="${basedir}/data"/>
<property name="docs" value="${basedir}/docs"/>
<property name="packages" value="${basedir}/packages"/>
<property name="src" value="${basedir}/src"/>
<property name="version" value="0.95"/>

<target name="init">
<tstamp/>
<mkdir dir="${packages}"/>
<mkdir dir="${classes}"/>
<mkdir dir="${data}"/>
<mkdir dir="${docs}"/>
</target>

<target name="compileClient" depends="init,docs">
<javac srcdir="${src}" destdir="${classes}"
includes="*Client*"
excludes="*Server*"/>
</target>

<target name="docs" depends="init">
<javadoc sourcepath="${src}" destdir="${docs}">
<fileset dir="${src}" defaultexcludes="yes">
<include name="*" />
</fileset>
</javadoc>
</target>

<target name="makeClientJar" depends="compileClient">
<jar jarfile="${packages}/client.${TODAY}.jar"
basedir="${classes}"
includes="**/*Client*"
excludes="**/*Server*">
<manifest>
<attribute name="Class-Path" value="${classes}.src"/>
<attribute name="Main-Class" value="src.EchoClient"/>
<attribute name="Build-By" value="${user.name}"/>

<section name="common">
<attribute name="Specification-Title" value="My
Manifest File"/>
<attribute name="Specification-Version"
value="${version}"/>
<attribute name="Specification-Vendor"
value="Kamil Corp."/>
<attribute name="Implementation-Title"
value="common"/>
<attribute name="Implementation-Version"
value="${version} ${TODAY}"/>
<attribute name="Implementation-Vendor"
value="Kamil Corp."/>
</section>
<section name="common/class1.class">
<attribute name="Sealed" value="false"/>
</section>
</manifest>
</jar>
</target>

<target name="run-client" depends="makeClientJar">
<java classname="src.EchoClient"
classpath="${packages}/client.${TODAY}.jar"
fork="true">
</java>
</target>

</project>

src/EchoClient.java
import java.io.*;
import java.net.*;
import java.util.*;

public class EchoClient {
public static void main(String[] args) throws IOException {

//declare variables used in the program
Socket echoSocket = null;
PrintWriter out = null;
BufferedReader in = null;
String host = "localhost";

System.out.println("Connecting...");

try {
//create Socket object and connect it to port 7 of the
host
echoSocket = new Socket(host, 7);
//create output stream for the created Socket
out = new PrintWriter(echoSocket.getOutputStream(),true);
//create input stream for the created Socket
in = new BufferedReader(new
InputStreamReader(echoSocket.getInputStream()));
} catch (UnknownHostException e) {
System.err.println("Don't know about host: "+ host);
System.exit(1);
} catch (IOException e) {
System.err.println("Couldn't get I/O for "
+ "the connection to: "+ host);
System.exit(1);
}

System.out.println("Connected !");

BufferedReader stdIn = new BufferedReader(new
InputStreamReader(System.in));

String target = "quit";

System.out.println("Please enter phrase (quit ends session):
");

String userInput = stdIn.readLine();

//continue echoing messages until user inputs quit
while (!userInput.equals(target)) {
long timeStarted = System.currentTimeMillis();
out.println(userInput);
System.out.println("echo: " + in.readLine());
long timeFinished =
System.currentTimeMillis()-timeStarted;
System.out.println("It took "+timeFinished+" ms for the
message to come back");
userInput=stdIn.readLine();
}

out.close();
in.close();
stdIn.close();
echoSocket.close();

}
}

Thanks for help.

 

[Neil Campbell]

Hello,

I am trying to run simple EchoClient program on my linux machine that
connects to the port 7 of the host.  It works perfectly from the
command line.  However when I try to run it from Ant I get
NullPointerException.  It seems that Ant has control over input and
output stream.  Question is:  Is there any way that Ant can hand over
the control over streams to the program that is currently running?

Hi,

I'm not sure if this will help, but the java task has options which allow
you to set specific files to use for standard input, output, and error:

http://ant.apache.org/manual/CoreTasks/java.html

I'm not sure if you can use Ant's standard input though.