I know that running unstable runs the risk of broken software, but I've been very happy with Sid since the days of Bo and Hamm (have I really been running Debian for 20 years?!).
But it seems to be biting me lately. A couple of months ago I decided to do a little self-learning of Java and/or Julia and/or Python, and it wasn't long before I thought I might get my feet wet with an IDE or two. At the time, playing with Java, Netbeans and Eclipse seemed the way to go, but on two or three different Sid boxes, I could get neither to work. So I moved on to Julia and Python. Now, a couple of months later, I figured the problems with Netbeans and Eclipse may have been ironed out.
But, nope.
Eclipse has improved though; it'll start up now, and let me do some of the tutorial (provided I find it online outside of Eclipse; trying to get to it from within the Eclipse options results in a "not found" error).
But that's all background. Here's my issue. All the tutorials/etc that I've found indicate I should be finding Java-related buttons, etc, within Eclipse, such as when going to Window/Preferences, but such items don't exist. As far as I can tell, Java is installed on the Debian box; Eclipse just isn't recognizing it.
i A default-jdk - Standard Java or Java compatible Development Kit
i A default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)
i A default-jdk-headless - Standard Java or Java compatible Development Kit (headless)
i A openjdk-10-doc - OpenJDK Development Kit (JDK) documentation
i A openjdk-10-jdk - OpenJDK Development Kit (JDK)
i A openjdk-10-jdk-headless - OpenJDK Development Kit (JDK) (headless)
i A openjdk-10-jre - OpenJDK Java runtime, using Hotspot JIT
i A openjdk-10-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
i A openjdk-11-jdk-headless - OpenJDK Development Kit (JDK) (headless)
i A openjdk-11-jre - OpenJDK Java runtime, using Hotspot JIT
i A openjdk-11-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
i A openjdk-8-jdk - OpenJDK Development Kit (JDK)
i A openjdk-8-jdk-headless - OpenJDK Development Kit (JDK) (headless)
i A openjdk-8-jre - OpenJDK Java runtime, using Hotspot JIT
i A openjdk-8-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
i A openjdk-9-jre - OpenJDK Java runtime, using Hotspot JIT
i A openjdk-9-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
westk@westkent64:~$
i A eclipse-jdt - Eclipse Java Development Tools (JDT)
i A eclipse-pde - Eclipse Plug-in Development Environment (PDE)
i A eclipse-platform - Eclipse platform without development plug-ins
i A eclipse-platform-data - Eclipse platform without development plug-ins (data)
i A eclipse-rcp - Eclipse Rich Client Platform (RCP)
i A libeclipse-core-contenttype-java - Eclipse Content Mechanism
i A libeclipse-core-expressions-java - Eclipse _expression_ Language
i A libeclipse-core-filesystem-java - Eclipse Core File Systems
i A libeclipse-core-jobs-java - Eclipse Core Jobs
i A libeclipse-core-runtime-java - Eclipse Core Runtime
i A libeclipse-osgi-java - Eclipse OSGi System Bundle
i A libeclipse-osgi-services-java - Eclipse OSGi Service Interfaces and Classes
i A libeclipse-osgi-util-java - Eclipse OSGi Utility Classes
i A libeclipselink-java - Eclipse Persistence Services Project
westk@westkent64:~$
westk@westkent64:~$ which java
/usr/bin/java
westk@westkent64:~$ which javac
/usr/bin/javac
westk@westkent64:~$ which javaws
/usr/bin/javaws
westk@westkent64:~$ ls -lah /usr/bin/java
lrwxrwxrwx 1 root root 22 Mar 22 2017 /usr/bin/java -> /etc/alternatives/java
lrwxrwxrwx 1 root root 43 Aug 7 21:16 /etc/alternatives/java -> /usr/lib/jvm/java-11-openjdk-amd64/bin/java
westk@westkent64:~$ java --version
openjdk 11 2018-09-25
OpenJDK Runtime Environment (build 11+28-Debian-3)
OpenJDK 64-Bit Server VM (build 11+28-Debian-3, mixed mode, sharing)
Any help would be appreciated.