import eclipse 3.1 M4 compiler

[org.ibex.tool.git] / src / org / eclipse / jdt / internal / compiler / flow / FlowContext.java

diff --git a/src/org/eclipse/jdt/internal/compiler/flow/FlowContext.java b/src/org/eclipse/jdt/internal/compiler/flow/FlowContext.java
index 340781f..46b46a5 100644 (file)
--- a/src/org/eclipse/jdt/internal/compiler/flow/FlowContext.java
+++ b/src/org/eclipse/jdt/internal/compiler/flow/FlowContext.java
@@ -13,11 +13,13 @@ package org.eclipse.jdt.internal.compiler.flow;
 import org.eclipse.jdt.core.compiler.CharOperation;
 import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration;
 import org.eclipse.jdt.internal.compiler.ast.ASTNode;
+import org.eclipse.jdt.internal.compiler.ast.Expression;
 import org.eclipse.jdt.internal.compiler.ast.Reference;
 import org.eclipse.jdt.internal.compiler.ast.SubRoutineStatement;
 import org.eclipse.jdt.internal.compiler.ast.TryStatement;
 import org.eclipse.jdt.internal.compiler.codegen.Label;
 import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
+import org.eclipse.jdt.internal.compiler.lookup.LocalVariableBinding;
 import org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding;
 import org.eclipse.jdt.internal.compiler.lookup.Scope;
 import org.eclipse.jdt.internal.compiler.lookup.TypeBinding;
@@ -167,7 +169,8 @@ public class FlowContext implements TypeConstants {
                                
                        traversedContext.recordReturnFrom(flowInfo.unconditionalInits());
                        if (traversedContext.associatedNode instanceof TryStatement){
-                               flowInfo = flowInfo.copy().addInitializationsFrom(((TryStatement) traversedContext.associatedNode).subRoutineInits);
+                               TryStatement tryStatement = (TryStatement) traversedContext.associatedNode;
+                               flowInfo = flowInfo.copy().addInitializationsFrom(tryStatement.subRoutineInits);
                        }
                        traversedContext = traversedContext.parent;
                }
@@ -265,7 +268,8 @@ public class FlowContext implements TypeConstants {
 
                        traversedContext.recordReturnFrom(flowInfo.unconditionalInits());
                        if (traversedContext.associatedNode instanceof TryStatement){
-                               flowInfo = flowInfo.copy().addInitializationsFrom(((TryStatement) traversedContext.associatedNode).subRoutineInits);
+                               TryStatement tryStatement = (TryStatement) traversedContext.associatedNode;
+                               flowInfo = flowInfo.copy().addInitializationsFrom(tryStatement.subRoutineInits);
                        }
                        traversedContext = traversedContext.parent;
                }
@@ -427,13 +431,18 @@ public class FlowContext implements TypeConstants {
                // default implementation: do nothing
        }
 
-       boolean recordFinalAssignment(
+       protected boolean recordFinalAssignment(
                VariableBinding variable,
                Reference finalReference) {
 
                return true; // keep going
        }
 
+       protected boolean recordNullReference(Expression expression, int status) {
+
+               return false; // keep going
+       }
+       
        public void recordReturnFrom(FlowInfo flowInfo) {
                // default implementation: do nothing
        }
@@ -455,6 +464,38 @@ public class FlowContext implements TypeConstants {
                }
        }
 
+       public void recordUsingNullReference(Scope scope, LocalVariableBinding local, Expression reference, int status, FlowInfo flowInfo) {
+
+               if (!flowInfo.isReachable()) return;
+
+               switch (status) {
+                       case FlowInfo.NULL :
+                               if (flowInfo.isDefinitelyNull(local)) {
+                                       scope.problemReporter().localVariableCanOnlyBeNull(local, reference);
+                                       return;
+                               } else if (flowInfo.isDefinitelyNonNull(local)) {
+                                       scope.problemReporter().localVariableCannotBeNull(local, reference);                            
+                                       return;
+                               }
+                               break;
+                       case FlowInfo.NON_NULL :
+                               if (flowInfo.isDefinitelyNull(local)) {
+                                       scope.problemReporter().localVariableCanOnlyBeNull(local, reference);                           
+                                       return;
+                               }
+                               break;
+               }
+               
+               // for initialization inside looping statement that effectively loops
+               FlowContext context = this;
+               while (context != null) {
+                       if (context.recordNullReference(reference, status)) {
+                               return; // no need to keep going
+                       }
+                       context = context.parent;
+               }
+       }
+       
        void removeFinalAssignmentIfAny(Reference reference) {
                // default implementation: do nothing
        }