Jaspersoft Studio 6.2 Build Path Warning

If you are new to the Eclipes environment and to Jaspersoft Studio, this complete answer will help you achieve success in removing the warning.

With the project active in the Design view, select Project from the main menu bar and the Properties option at the bottom of the dropdown. If your project is not active, Properties will be disabled. To activate the Properties option, select the Design view near the lower one third of the IDE page in the middle pane, then click inside the page area of your design view. Not Properties in the Project menu should be active.
In the far left panel of the dialog, select the "Java Build Path" from the available options.
Add Library from the buttons in the far right of the dialog.
Select "JRE System Library" from the options, and the Next > button.
Select the "Execution environment:" radio option, which should automatically populate the JRE System Library available. If it doesn't, try using the "Alternate JRE:". All of this step assumes that you have a JRE installed on your system, which is not the default library installed by Jaspersoft Studio.
Select the Finish button.
This step is important, because if you don't remove the library installed in your project by default, the warning will not disappear. Select JRE System Library[J2SE 1.6] from the middle section labeled "JARs and class folders on the build path:", select the Remove button on the right.
Select the Apply button, then the OK button.

At this point, clean your project and rebuild it. The warning should be gone.

Even though this answer is specific to Jaspersoft Studio, and the JRE System Library[J2SE 1.6], you may be able to extrapolate this solution to other platforms, but this assumes the interface has not significantly changed.

Warning - Build path specifies execution environment J2SE-1.4

In Eclipse from your project:

Right-click on your project
Click Properties
Java build path: Libraries; Remove the "JRE System Library[J2SE 1.4]"
Click Add Library -> JRE System Library
Select the new "Execution Environment" or Workspace default JRE

Jasper Subreport Not Displayed

I solved the issue by updating the JRE. I followed the step in this link https://stackoverflow.com/questions/34613580/jaspersoft-studio-6-2-build-path-warning

Problems installing Jasperserver with Powershell. ANT can't see Java

Both SetEnvironmentVariable(..., "Machine") and setx set the variable in the registry. This value is used for future processes launched by explorer (such as after a reboot), but it is NOT set for the current process or its children. Your script needs to set the variables for the current process.

Using the .NET syntax:

[Environment]::SetEnvironmentVariable("JAVA_HOME", "C:\Program Files\Java\jdk1.8.0_91", "Process")

Or, using PS syntax

$env:JAVA_HOME = "C:\Program Files\Java\jdk1.8.0_91"

Jaspersoft Studio 6.2 Build Path Warning