Created attachment 156114 [details]
Shows some examples of this issue

See the code

//| marks the caret, where to start CC
/*a*/java.util.List<String> list=| 
/*b*/System.out.println(|);
/*c*/System.out.println("foo="+|);

Case A:
-------
ACTUAL:
for /*a*/+/*b*/ methods with return type 'void' are proposed, using them leads to compile errors
EXPECTED 
for /*a*/+/*b*/ methods with return type 'void' are NOT proposed

Case B:
-------
ACTUAL:
for /*a*/ methods with return type 'int|long|boolean|short' (primitive types) are proposed, using them leads to compile errors (it is a dead end)

EXPECTED:
those are not proposed (but take care: they are still allowed when the target type is String [/*c*/] or is an Object [/*b*/])

Case C:
-------
ACTUAL:
for /*a*/+/*b*/+/*c*/ keywords like 'boolean|int|double|true|false|...' are proposed, using them leads to compile errors
EXPECTED 
those are not proposed (but take care: sometimes true/false are allowed [if the targettype is Boolean or Object)



See also the screenshot


Product Version: NetBeans IDE 8.1 Beta (Build 201507231027)
Java: 1.8.0_60-ea; Java HotSpot(TM) 64-Bit Server VM 25.60-b23
Runtime: Java(TM) SE Runtime Environment 1.8.0_60-ea-b25
System: Windows 7 version 6.1 running on amd64; Cp1252; en_US (nb)