Eclipse – Red exclamation mark in Eclipse with mercurial

eclipsemercurial

I have imported a project with Mercurial (hg clone …).
When opening it with Eclipse, a red exclamation mark appears by the project's name in the Project Explorer, and it cannot be built. Silly messages like "import java.util cannot be resolved" appear, and errors in files are not marked in the Package Explorer.

How can I resolve this?

Best Answer

Check the problem view. By exclamation it is usually means a problem with build path

Check the Build Path of the project by right clicking the project and select Build Path -> Configure Build Path.

One problem I often encountered is different people using different Java SDK and so when the exact SDK is not available in your machine, you need to change to your Java SDK (via JRE System Library -> Alternate JRE). A better way to avoid this problem is to always select the JRE System Library from Workspace default JRE or Execution Environment.

Related Solutions

Git – the Difference Between Mercurial and Git

These articles may help:

Git vs. Mercurial: Please Relax (Git is MacGyver and Mercurial is James Bond)
The Differences Between Mercurial and Git

Edit: Comparing Git and Mercurial to celebrities seems to be a trend. Here's one more:

Git is Wesley Snipes, Mercurial is Denzel Washington

Eclipse – How to you speed up Eclipse

The three most influential factors for Eclipse speed are:

Using the latest version of Eclipse (2020-06 as on 26 June 2020)
Note that David Balažic's comment (July 2014) contradicts that criteria which was working six years ago:

The "same" workspace in Indigo (3.7.2) SR2 loads in 4 seconds, in Kepler SR2 (4.3.2) in 7 seconds and in Luna (4.4.0) in 10 seconds. All are Java EE bundles. Newer versions have more bundled plugins, but still the trend is obvious. (by "same" workspace I mean: same (additionally installed) plugins used, same projects checked out from version control).

Launching it with the latest JDK (Java 14 at the time of writing, which does not prevent you to compile in your Eclipse project with any other JDK you want: 1.4.2, 1.5, 1.6 older...)
```
  -vm jdk1.6.0_10\jre\bin\client\jvm.dll
```
Configuring the eclipse.ini (see this question for a complete eclipse.ini)
```
  -Xms512m
  -Xmx4096m
  [...]
```

The Xmx argument is the amount of memory Eclipse will get (in simple terms). With -Xmx4g, it gets 4 GB of RAM, etc.

Note:

Referring to the jvm.dll has advantages:

Splash screen coming up sooner.
Eclipse.exe in the process list instead of java.exe.
Firewalls: Eclipse wants access to the Internet instead of Java.
Window management branding issues, especially on Windows and Mac.

Dec. 2020, Udo conforms in the comments

From version 4.8 (Photon) an up there was a steady speed gain after each version.
The main platform was optimized every release to load faster, enable more features for the dark theme and to add more features for newer Java versions for the Java development tools.
Especially with-in the last 3 versions the startup time was increased a lot. There should be a significant increase in start-up time with the newest version of Eclipse 2020-12.

In my experience it started a lot faster with each new version.
But: There are still plug-ins which do not follow the new way of using the Eclipse API and are therefore still slow to start.
Since the change to Java 11 as the minimum runtime version starting from Eclipse version 2020-09 at least the core system uses the newer features of the JVM. It is up to the providers of the other plug-ins to upgrade to newer APIs and to use the full power of modern CPUs (e.g. concurrent programming model).

Best Answer

Related Solutions

Git – the Difference Between Mercurial and Git

Eclipse – How to you speed up Eclipse

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