How long screen command runs?

Does screen command run forever?

Suppose I have following command inserted at my putty shell followed by screen

# screen
# export JAVA_HOME=/usr/java/jdk1.6.0_21
# export ANT_HOME=/usr/ant
# export PATH=$PATH:$JAVA_HOME/bin:$ANT_HOME/bin
# export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
# cd /opt/red5/dist
# ./red5.sh > start.log &
If I input this commands followed by screen , will be paths and home paths saved and RED5 process will run forever?

[/code]