Eclipse reports the following two errors:

The project cannot be built until build path errors are resolved HelloWord Unknown Java Problem

Unbound classpath container: 'JRE System Library [JavaSE-1.7]' in project 'java project name' java project name Build path Build Path Problem

it seems that MyEclipse can't find the classpath of Java 1.7, so I checked the Java environment variable settings, but found no problem. Then I had to go to Google to see if I could find a solution, and finally in stack overflow   I found this post on. The main idea of the solution is as follows:

1. Check whether JDK is installed correctly

2. After correct installation, open MyEclipse/eclipse window - > Preferences -> Java –> Configured with installed jres

the specific configuration method is very simple:

is to click "add" on the right side of the window, then add a "standard VM" (which should mean standard virtual machine), and then click "next"

in the "JRE home" line, click "directory..." on the right to find your Java installation path, such as "C: \ program files \ Java \ jdk1.7.0"_09”