You can enable this in Window – Preferences – General – Workspace – Refresh Automatically (called Refresh using native hooks or polling in newer builds)

The only reason I can think why this isn’t enabled by default is performance related.
For example, refreshing source folders automatically might trigger a build of the workspace. Perhaps some people want more control over this.
There is also an article on the Eclipse site regarding auto refresh.
Basically, there is no external trigger that notifies Eclipse of files changed outside the workspace. Rather a background thread is used by Eclipse to monitor file changes that can possibly lead to performance issues with large workspaces.
Related Posts:
- How to solve could not create the virtual machine error of Java Virtual Machine Launcher?
- How to solve could not create the virtual machine error of Java Virtual Machine Launcher?
- Editor does not contain a main type
- The superclass “javax.servlet.http.HttpServlet” was not found on the Java Build Path
- The superclass “javax.servlet.http.HttpServlet” was not found on the Java Build Path
- Eclipse: Enable autocomplete / content assist
- java.lang.NoClassDefFoundError: org/hamcrest/SelfDescribing
- “insufficient memory for the Java Runtime Environment ” message in eclipse
- Control an Arduino with Java
- How do I resolve the “java.net.BindException: Address already in use: JVM_Bind” error?
- Opening JSF Facelets page shows “This XML file does not appear to have any style information associated with it.”
- web.xml is missing and
is set to true - The program can’t start because cygwin1.dll is missing… in Eclipse CDT
- Eclipse C++ : “Program “g++” not found in PATH”
- Unbound classpath container in Eclipse
- ‘cannot open git-upload-pack’ error in Eclipse when cloning or pushing git repository
- “Server Tomcat v7.0 Server at localhost failed to start” without stack trace while it works in terminal
- java.lang.ClassNotFoundException: com.sun.jersey.spi.container.servlet.ServletContainer
- “Server Tomcat v7.0 Server at localhost failed to start” without stack trace while it works in terminal
- web.xml is missing and
is set to true – web.xml is there and can’t edit deployment assembly - eclipse won’t start – no java virtual machine was found
- How to solve “Plugin execution not covered by lifecycle configuration” for Spring Data Maven Builds
- Eclipse returns error message “Java was started but returned exit code = 1”
- Ant “JAVA_HOME does not point to the JDK” – but it does
- Program “make” not found in PATH
- Eclipse internal error while initializing Java tooling
- web.xml is missing and
is set to true - How to clear console in Java – Eclipse
- Eclipse keyboard shortcut to indent source code to the left?
- eclipse for chrome?
- Can eclipse be configured to automatically fix missing Imports?
- Program “make” not found in PATH
- Importing Maven project into Eclipse
- How to show the Project Explorer window in Eclipse?
- Eclipse Mars vs Luna
- Push eclipse project to GitHub with EGit
- How to open an existing project in Eclipse?
- CodePro Analytix: Where to find the plugin
- How to open Console window in Eclipse?
- Some projects cannot be imported because they already exist in the workspace error in Eclipse
- Java error no lwjgl64 in path?
- Can’t start Eclipse – Java was started but returned exit code=13
- Eclipse IDE for Java – Full Dark Theme
- “Error occurred during initialization of VM; Could not reserve enough space for object heap” using -Xmx3G
- A JNI error has occurred, please check your installation and try again in Eclipse x86 Windows 8.1
- “Error occurred during initialization of VM; Could not reserve enough space for object heap” using -Xmx3G
- Editor does not contain a main type in Eclipse [duplicate]
- undefined reference to `WinMain@16′
- JRE Missing when installing eclipse
- Server Tomcat v9.0 Server at localhost failed to start
- Cannot find “Package Explorer” view in Eclipse
- what does Dead Code mean under Eclipse IDE Problems Section
- Eclipse: Java was started but returned error code=13
- How to change a package name in Eclipse?
- Eclipse “Error: Could not find or load main class”
- Error: Selection does not contain a main type
- Integrate Ant builder into Eclipse: Error “Variable references empty selection”
- eclipse won’t start – no java virtual machine was found
- Access restriction: The type ‘Application’ is not API (restriction on required library rt.jar)
- how to run the command mvn eclipse:eclipse
- Eclipse error, “The selection cannot be launched, and there are no recent launches”
- The import org.apache.commons cannot be resolved in eclipse juno
- How do I set up Eclipse/EGit with GitHub?
- Failed to load the JNI shared Library (JDK)
- Eclipse java debugging: source not found
- No appenders could be found for logger(log4j)?
- Syntax error on token(s), misplaced construct(s)
- Error occurred during initialization of VM (java/lang/NoClassDefFoundError: java/lang/Object)
- What does this GCC error “… relocation truncated to fit…” mean?
- Java project in Eclipse: The type java.lang.Object cannot be resolved. It is indirectly referenced from required .class files
- Member declaration not found
- Cross compiler prefix and path in eclipse
- “The import org.springframework cannot be resolved.”
- Resource leak: ‘in’ is never closed
- Java console program
- “Source folder is not a Java project” error in eclipse
- Cannot be resolved to a variable error in Eclipse
- Using JavaFX in JRE 8, “Access restriction” error
- Eclipse Problems View not showing Errors anymore
- “Cannot be resolved to a type” when attempting to use Scanner
- java eclipse red exclamation mark
- Eclipse is executing the wrong Java file
- Eclipse: JVM terminated. Exit code=2
- “insufficient memory for the Java Runtime Environment ” message in eclipse
- Unknown version of Tomcat was specified in Eclipse
- Which Eclipse IDE version to choose?
- How to configure Eclipse CDT for cmake?
- Java says this method has a constructor name
- How can i fix this equals on primitive type(int)
- Error :- java runtime environment JRE or java development kit must be available in order to run eclipse
- How fix Error:java.util.concurrent.ExecutionException: com.android.ide.common.process.ProcessException:
- Maven dependency update on commandline
- The import javax.servlet can’t be resolved
- Eclipse EGit Checkout conflict with files: – EGit doesn’t want to continue
- “please check gdb is codesigned – see taskgated(8)” – How to get gdb installed with homebrew code signed?
- How to solve “Unresolved inclusion:
” in a C++ file in Eclipse CDT? - How do I enable index downloads in Eclipse for Maven dependency search?
- Check if a database is well installed
- WordPress site under localhost is disassociated with the code
- Is it a good idea to edit WordPress within Eclipse? [closed]