Red Hat Developer Tools 1 Using Eclipse 4.18

Red Hat Developer Tools 1

Using Eclipse 4.18

Installing Eclipse 4.18 and the first steps with the application

Last Updated: 2021-02-18

Red Hat Developer Tools 1 Using Eclipse 4.18

Installing Eclipse 4.18 and the first steps with the application

Eva-Lotte Gebhardt

egebhar[email protected]om

Olga Tikhomirova

otikhomi@redhat.com

Peter Macko

Kevin Owen

Yana Hontyk

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Abstract

Information for users installing and starting to use Red Hat Developer Tools.

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Table of Contents

MAKING OPEN SOURCE MORE INCLUSIVE

CHAPTER 1. ECLIPSE 4.18

1.1. ENABLING ACCESS TO ECLIPSE RPMS ON RED HAT ENTERPRISE LINUX 7

Optional: Enabling the Red Hat Developer Tools debuginfo repositories

Additional resources

1.2. INSTALLING ECLIPSE

1.2.1. Installing additional Eclipse components

1.2.1.1. Installing additional Eclipse components using the Install New Software wizard

1.2.1.2. Installing additional Eclipse components using Eclipse Marketplace

1.2.1.2.1. Example: Installing C and C++ Development Tooling (CDT) using the Eclipse Marketplace Client

1.2.1.3. Installing additional Eclipse components using the command-line interface

1.2.1.3.1. Example: Installing Eclipse C and C++ Development Tools using the command-line interface

Additional resources

1.3. STARTING ECLIPSE

1.3.1. Starting Eclipse from the GUI

1.3.2. Starting Eclipse from the command-line interface

1.4. ECLIPSE COMPONENTS

Additional resources

1.5. CHANGES IN ECLIPSE 4.18

Additional resources

1.6. KNOWN ISSUES IN ECLIPSE 4.18

Table of Contents

Red Hat Developer Tools 1 Using Eclipse 4.18

MAKING OPEN SOURCE MORE INCLUSIVE

Red Hat is committed to replacing problematic language in our code, documentation, and web

properties. We are beginning with these four terms: master, slave, blacklist, and whitelist. Because of the

enormity of this endeavor, these changes will be implemented gradually over several upcoming releases.

For more details, see our CTO Chris Wright’s message .

MAKING OPEN SOURCE MORE INCLUSIVE

CHAPTER 1. ECLIPSE 4.18

Red Hat Developer Tools on Red Hat Enterprise Linux 7 is an offering for developers on the RHEL

platform that includes Eclipse 4.18, which is based on the Eclipse Foundation’s 2020-12 release train.

The Eclipse development environment provides tools for each phase of the development process.

Eclipse 4.18 on RHEL 7 supports Java development.

To learn more about Eclipse, see the main Eclipse foundation page .

Sample Eclipse session

Eclipse provides a graphical development environment and is therefore an alternative to using the

command-line interface.

For an overview of how to develop applications for Red Hat JBoss Middleware or for support of

OpenShift Tools, see Red Hat Developer Studio.

1.1. ENABLING ACCESS TO ECLIPSE RPMS ON RED HAT

ENTERPRISE LINUX 7

Eclipse is part of the Red Hat Developer Tools content set for RHEL 7. To install Eclipse, enable the

Red Hat Developer Tools, Red Hat Software Collections, and Optional repositories using the Red Hat

Subscription Management utility.

Prerequisites

The host must be registered and attached to a subscription.

For more information on registering your system using Red Hat Subscription Management and

Red Hat Developer Tools 1 Using Eclipse 4.18

For more information on registering your system using Red Hat Subscription Management and

associating it with subscriptions, see the Red Hat Subscription Management collection of

guides.

Procedure

Choose the system variant, either workstation or server, to use in the following commands. Red Hat

recommends to choose server for access to the widest range of development tools.

1. Enable the rhel-7-variant-devtools-rpms repository to access Red Hat Developer Tools:

# subscription-manager repos --enable rhel-7-variant-devtools-rpms

2. Enable the rhel-variant-rhscl-7-rpms repository to access Red Hat Software Collections:

# subscription-manager repos --enable rhel-variant-rhscl-7-rpms

3. Enable the rhel-7-variant-optional-rpms repository to access additional components:

# subscription-manager repos --enable rhel-7-variant-optional-rpms

Optional: Enabling the Red Hat Developer Tools debuginfo repositories

The Red Hat Developer Tools offering also provides debuginfo packages for all architecture-

dependent RPMs in the repositories. These packages are useful for core-file analysis and for debugging

Eclipse itself.

Procedure

Enable the Red Hat Developer Tools debuginfo repositories and replace variant with the

Red Hat Enterprise Linux system variant (server or workstation):

# subscription-manager repos --enable rhel-7-variant-devtools-debug-rpms

Enable the Red Hat Software Collections debuginfo repository:

# subscription-manager repos --enable rhel-__variant__-rhscl-7-debug-rpms

Additional resources

For details on installing, understanding, and using the debuginfo packages, refer to Debugging

a Running Application.

For more information on registering your system using Red Hat Subscription Management and

associating it with subscriptions, see the Red Hat Subscription Management collection of

guides.

For detailed instructions on managing a subscription to Red Hat Software Collections, see the

Red Hat Developer Toolset User Guide Section 1.4. Getting Access to Red Hat Developer

Toolset.

1.2. INSTALLING ECLIPSE

The following section describes how to install Eclipse.

NOTE

CHAPTER 1. ECLIPSE 4.18

NOTE

Eclipse is available only on the AMD64 and Intel 64 architecture.

Prerequisites

On RHEL 7, the repositories must be enabled as per Section 1.1, “Enabling access to Eclipse

RPMs on Red Hat Enterprise Linux 7”.

Procedure

On RHEL 7, run the following command:

# yum install rh-eclipse

1.2.1. Installing additional Eclipse components

Eclipse 4.18 on RHEL 7 supports Java development. To install more components from the upstream

repositories, for example to support the C and C++ languages, use the Install New Software wizard,

Eclipse Marketplace Client, or the command-line interface.

NOTE

Installing additional Eclipse components is not possible without access to the internet.

1.2.1.1. Installing additional Eclipse components using the Install New Software wizard

Procedure

To use the Install New Software wizard for the installation of additional components, in the main

menu click Help > Install New Software and follow the instructions on the screen.

1.2.1.2. Installing additional Eclipse components using Eclipse Marketplace

To use the Marketplace Client for the installation of additional components, follow the instructions in

Section 1.2.1.2.1, “Example: Installing C and C++ Development Tooling (CDT) using the Eclipse

Marketplace Client”.

1.2.1.2.1. Example: Installing C and C++ Development Tooling (CDT) using the Eclipse Marketplace

Client

Procedure

1. From the main menu, select Help > Eclipse Marketplace.

2. In Eclipse Marketplace, use the Find field to search for the wanted component, in this case CDT,

and press Go.

Red Hat Developer Tools 1 Using Eclipse 4.18

3. Click the Install button to start the installation and follow the instructions on the screen.

1.2.1.3. Installing additional Eclipse components using the command-line interface

Red Hat recommends using Eclipse Marketplace or the Install New Software wizard to install additional

components to Eclipse. However, it is possible to install components from the command line using the

p2 director application.

To use the command-line interface for the installation of additional components, follow the instructions

in Section 1.2.1.3.1, “Example: Installing Eclipse C and C++ Development Tools using the command-line

interface”.

1.2.1.3.1. Example: Installing Eclipse C and C++ Development Tools using the command-line interface

Prerequisites

Eclipse is not running.

Procedure

1. In the command-line interface, run the following command:

$ scl enable rh-eclipse 'eclipse -noSplash -application org.eclipse.equinox.p2.director -

repository https://download.eclipse.org/releases/2020-12 -i org.eclipse.cdt.feature.group'

CHAPTER 1. ECLIPSE 4.18

2. Start Eclipse.

Eclipse C/C++ Development Tools is installed.

WARNING

Running the p2 director application as root causes significant problems for the RPM

consistency. Never run the p2 director application as root.

Additional resources

For a list of available components, see Section 1.4, “Eclipse Components”.

For further information on the p2 director application, see Installing software using the p2

director application in the online documentation or the built-in help system of Eclipse.

1.3. STARTING ECLIPSE

1.3.1. Starting Eclipse from the GUI

To start Eclipse from the GUI, complete the following steps:

Click Applications > Programming > Red Hat Eclipse.

1.3.2. Starting Eclipse from the command-line interface

To start Eclipse from the command-line, type the following at a shell prompt:

On RHEL 7:

$ scl enable rh-eclipse eclipse

While starting, Eclipse prompts you to select a workspace directory for your projects. You can use

~/workspace/, the default option, or click Browse and select a custom directory. You can also select

Use this as the default and do not ask again to prevent Eclipse from displaying this dialog box again.

Click OK to confirm the selection and proceed with the start.

1.4. ECLIPSE COMPONENTS

The Eclipse development environment is provided as a set of RPM packages. The set contains the

following Eclipse components:

Table 1.1. Eclipse Components on RHEL 7

Package Description

rh-eclipse-eclipse-egit EGit, a team provider for Eclipse, provides features

and plug-ins for interaction with Git repositories.



Red Hat Developer Tools 1 Using Eclipse 4.18

rh-eclipse-eclipse-emf The Eclipse Modeling Framework (EMF) enables you

to build applications based on a structured data

model.

rh-eclipse-eclipse-gef The Graphical Editing Framework (GEF) enables you

to create a rich graphical editor from an existing

application model.

rh-eclipse-eclipse-jdt The Eclipse Java development tools (JDT) plug-in.

rh-eclipse-eclipse-jgit JGit, a Java implementation of the Git revision

control system.

rh-eclipse-eclipse-mpc The Eclipse Marketplace Client.

rh-eclipse-eclipse-pde The Plugin Development Environment for developing

Eclipse plug-ins.

rh-eclipse-eclipse-subclipse Subclipse, a team provider for Eclipse allows you to

interact with Subversion repositories.

rh-eclipse-eclipse-webtools The Eclipse Webtools plug-ins.

Package Description

Additional resources

A detailed description of Eclipse and all its features is beyond the scope of this document. For more

information, see the following resources.

Installed documentation

Eclipse includes a built-in help system that provides extensive documentation for each

integrated feature and tool. It is accessible from Eclipse’s main menu: Help > Help Contents.

Other resources

For a list of selected features and improvements in the latest version of the Eclipse

development environment, see Section 1.5, “Changes in Eclipse 4.18” .

1.5. CHANGES IN ECLIPSE 4.18

Eclipse 4.18 ships with Red Hat Developer Tools and plug-ins from the 2020-12 release train that

provide a number of bug fixes and feature enhancements.

This section lists notable new features and compatibility changes in this release.

Significant package updates on RHEL 7

eclipse 4.17 → 4.18

Eclipse IDE and JDT/PDE plug-ins have been updated to version 4.18. For a more complete list of

CHAPTER 1. ECLIPSE 4.18

Eclipse IDE and JDT/PDE plug-ins have been updated to version 4.18. For a more complete list of

changes, see the Eclipse 4.18 – New and Noteworthy page. Notable enhancements include:

In the Console preference page it is now possible to select the new preference "Enable word

wrap".

In the Appearance preference page the new "System" theme is now available. It uses system

colors to integrate smoothly into your operating system or operating system theme.

Eclipse JDT has been updated to use JUnit 5.7.

New clean up options and code formatting options have been added to Java Development

Tools.

In the Arguments tab for Java-based launch configurations (Java Application, JUnit, and

others), you can now select the new checkbox to write arguments into an @argfile.

eclipse-egit/jgit 5.9.0 → 5.10.0

The Git integration plug-ins have been updated to version 5.10.0. For details, see the upstream EGit

5.10.0 release notes and JGit 5.10.0 release notes.

eclipse-m2e 1.16.2 → 1.17.1

The Maven integration plug-in has been updated to version 1.17.1.

Deprecated functionality on RHEL 7

Python development is no longer supported as part of Eclipse. It can be installed additionally from the

Install New Software wizard or Eclipse Marketplace.

Additional resources

For details on how to use the new features, see Eclipse Installed documentation.

1.6. KNOWN ISSUES IN ECLIPSE 4.18

This section details the known issues in Eclipse 4.18.

Known issues on RHEL 7

Initializing Eclipse Error Reporting System error

This error occurs when running a workspace created in an older version of Eclipse.

To work around this problem, start Eclipse with the -clean option to clear its dependency resolution

cache:

$ scl enable rh-eclipse "eclipse -clean"

Eclipse will start without this error message.

NullPointerExceptions

NullPointerExceptions can occur when you install a plug-in from a third-party update site. In that

case, Eclipse fails to start with a NullPointerException in the workspace log file.

To work around this problem, restart Eclipse with the -clean option to clear its dependency resolution

cache:

On RHEL 7:

Red Hat Developer Tools 1 Using Eclipse 4.18

$ scl enable rh-eclipse "eclipse -clean"

Eclipse will start normally.

The rh-eclipse-tycho package conflicts with the same package from earlier collections

For example: rh-eclipse48-tycho:

As a result, the installation of the rh-eclipse-tycho package may fail when the rh-eclipse48-tycho

package is already installed.

You only need Tycho if you want to build or rebuild Eclipse or its plug-ins need Tycho. If needed,

uninstall the rh-eclipse48-tycho package before installing the rh-eclipse-tycho package using this

command:

$ yum remove rh-eclipse48-tycho

The installation of the rh-eclipse-tycho package will now succeed.

The rh-eclipse-scldevel package conflicts with packages from earlier collections

For example: rh-maven36-scldevel:

As a result, the installation of the rh-maven36-scldevel package may fail when the rh-maven35-

scldevel package is already installed.

To solve this problem, uninstall the rh-maven35-scldevel package before installing the new version

of rh-eclipse-scldevel using this command:

$ yum remove rh-maven35-scldevel

The installation of rh-eclipse-scldevel will now succeed.

Incompatibilities between Eclipse Subclipse and base RHEL Subversion

Working copies of Subversion repositories created with Eclipse Subclipse are incompatible with the

base RHEL version of Subversion. Using the svn command on such working copies may result in the

following error:

$ svn up

svn: E155021: This client is too old to work with the working copy

To work around this problem, use the pure Java implementation of Subversion used by Eclipse

Subclipse on the command line:

# yum install rh-eclipse-svnkit-cli # Command line support for SVNKit

Now, use the jsvn command anywhere you would normally use the svn command:

$ jsvn up

Updating '.':

At revision 16476.

Lambda expression evaluation failed due to unexpected argument types

During compilation, some lambda expressions used in conditional breakpoints or Expression view are

CHAPTER 1. ECLIPSE 4.18

During compilation, some lambda expressions used in conditional breakpoints or Expression view are

falsely assigned an Object variable type.

For example, the expression lotteryNumbers.stream().anyMatch(a → a >= 42) evaluates the following

error message:

The operator >= is undefined for the argument type(s) Object, int

Red Hat Developer Tools 1 Using Eclipse 4.18