Eclipse Error: java.lang.CharSequence cannot be resolved
eclipse, java
Solution
Ensure that your Eclipse IDE supports Java 8:
The first Eclipse version supporting Java 8 was Eclipse Kepler SR2 (4.3.2) with an additional patch. (See: Installing Java™ 8 Support in Eclipse Kepler SR2, and the corresponding Marketplace Item that needs to be installed: Java 8 support for Eclipse Kepler SR2).
In my opinion you should udpate to the latest Eclipse Version.
With Luna SR2 (4.4.2) no additional patch is necessary.
Ensure the 1.8 JRE is available in your Workspace:
Windows > Preferences: Java > Installed JREs
If this is not the case you can add a new JRE with the add button.
Ensure that `JRE System Library` == `JavaSE-1.8` for your Project
In the Package Explorer, you should see the Java version:
If this is not correct you should open the context menu the `JRE System Library` item and select the `Properties` menu entry.
In your project you have a `.classpath` file (Use the `Navigator View` if you do not see the file), that should looks like this:
<?xml version="1.0" encoding="UTF-8"?>
<classpath>
<classpathentry kind="src" path="src"/>
<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
<classpathentry kind="output" path="bin"/>
</classpath>
Rebuild your project
Project Menu > Clean...
Select your project from the list or "Clean all projects" and "Start a build immediately"
See also:
- Explaination from @mkrakhin in his answer: The type java.lang.CharSequence cannot be resolved in package declaration
Problem
I'm getting a error trying to compile a simple code in Eclipse. I'm using jre8. For example, when I try to compile this code: ``` import java.util.ArrayList; import java.util.Collections; import java.util.List; public class MyProject { public static void main (String args[]) { List<String> myList = new ArrayList<String>(); myList.add("test"); myList.add("test2"); Collections.sort(myList); } } ``` I get a error in the `Collections.sort(myList);` line. The error is: ``` Exception in thread "main" java.lang.Error: Unresolved compilation problem: The type java.lang.CharSequence cannot be resolved. It is indirectly referenced from required .class files at project.Principal.main(Principal.java:14) ``` I have already opened eclipse Build Path, removed JRE System Library [jre8] and added it again. But didn't work! What can I do? Thanks! PS.: In the `Collections.sort(myList);` line eclipse shows this error: The type java.lang.CharSequence cannot be resolved. It is inderectly referenced from required .class files.