--- a/java.source/apichanges.xml	Sun Oct 30 12:32:59 2011 +0100
+++ a/java.source/apichanges.xml	Mon Oct 31 12:33:41 2011 +0100
@@ -108,6 +108,18 @@ 
     <!-- ACTUAL CHANGES BEGIN HERE: -->
 
     <changes>
+        <change id="TreeUtilities-isCompileTimeConstantExpression">
+             <api name="general"/>
+             <summary>Added <code>TreeUtilities.isCompileTimeConstantExpression</code>.</summary>
+             <version major="0" minor="91"/>
+             <date day="7" month="11" year="2011"/>
+             <author login="jlahoda"/>
+            <compatibility addition="yes" binary="compatible" deletion="no" deprecation="no" modification="no" semantic="compatible" source="compatible"/>
+             <description>
+                 Added <code>TreeUtilities.isCompileTimeConstantExpression</code> that tests whether the given expression is a compile-time constant.
+             </description>
+             <issue number="204435"/>
+        </change>
         <change id="CompilationInfo-cache">
              <api name="general"/>
              <summary>Added <code>CompilationInfo.getCachedValue</code>, <code>CompilationInfo.putCachedValue</code> and <code>CompilationInfo.CacheClearPolicy</code>.</summary>
--- a/java.source/nbproject/project.properties	Sun Oct 30 12:32:59 2011 +0100
+++ a/java.source/nbproject/project.properties	Mon Oct 31 12:33:41 2011 +0100
@@ -46,7 +46,7 @@ 
 javadoc.title=Java Source
 javadoc.arch=${basedir}/arch.xml
 javadoc.apichanges=${basedir}/apichanges.xml
-spec.version.base=0.90.0
+spec.version.base=0.91.0
 test.qa-functional.cp.extra=${refactoring.java.dir}/modules/ext/javac-api-nb-7.0-b07.jar
 test.unit.run.cp.extra=${o.n.core.dir}/core/core.jar:\
     ${o.n.core.dir}/lib/boot.jar:\
--- a/java.source/src/org/netbeans/api/java/source/TreeUtilities.java	Sun Oct 30 12:32:59 2011 +0100
+++ a/java.source/src/org/netbeans/api/java/source/TreeUtilities.java	Mon Oct 31 12:33:41 2011 +0100
@@ -1148,4 +1148,18 @@ 
             return list.size();
         }
     }
+
+    /**Checks whether the given expression is a compile-time constant, as per JLS 15.28.
+     * 
+     * @param expression the expression to check
+     * @return true if and only if the given expression represents a compile-time constant value
+     * @since 0.91
+     */
+    public boolean isCompileTimeConstantExpression(TreePath expression) {
+        Scope s = info.getTrees().getScope(expression);
+        TypeMirror attributeTree = attributeTree(expression.getLeaf(), s);
+        Type attributeTreeImpl = (Type) attributeTree;
+
+        return attributeTreeImpl != null && attributeTreeImpl.constValue() != null;
+    }
 }
--- a/java.source/test/unit/src/org/netbeans/api/java/source/TreeUtilitiesTest.java	Sun Oct 30 12:32:59 2011 +0100
+++ a/java.source/test/unit/src/org/netbeans/api/java/source/TreeUtilitiesTest.java	Mon Oct 31 12:33:41 2011 +0100
@@ -43,6 +43,7 @@ 
  */
 package org.netbeans.api.java.source;
 
+import com.sun.source.tree.AssignmentTree;
 import com.sun.source.tree.BlockTree;
 import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.LiteralTree;
@@ -53,7 +54,9 @@ 
 import com.sun.source.tree.Tree.Kind;
 import com.sun.source.tree.VariableTree;
 import com.sun.source.util.TreePath;
+import com.sun.source.util.TreePathScanner;
 import java.io.File;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
@@ -480,4 +483,19 @@ 
 
         assertFalse(info.getTreeUtilities().isStaticContext(s));
     }
+
+    public void testIsCompileTimeConstant() throws Exception {
+        prepareTest("Test", "package test; public class Test { private void m(String str) { int i; i = 1 + 1; i = str.length(); } }");
+
+        final List<Boolean> result = new ArrayList<Boolean>();
+
+        new TreePathScanner<Void, Void>() {
+            @Override public Void visitAssignment(AssignmentTree node, Void p) {
+                result.add(info.getTreeUtilities().isCompileTimeConstantExpression(new TreePath(getCurrentPath(), node.getExpression())));
+                return super.visitAssignment(node, p);
+            }
+        }.scan(info.getCompilationUnit(), null);
+
+        assertEquals(Arrays.asList(true, false), result);
+    }
 }