public SourceRange csp(JCTree tree) 
{
            if (tree == null) return null;
            tree.accept(this);
            if (result != null) {
                positions.put(tree, result);
            }
            return result;
}

Visitor method: compute source positions for a single node.

 public SourceRange csp(List<JCTree> trees) 
{
            if ((trees == null) || !(trees.nonEmpty())) return null;
            SourceRange list_sr = new SourceRange();
            for (List< ? extends JCTree > l = trees; l.nonEmpty(); l = l.tail) {
                list_sr.mergeWith(csp(l.head));
            }
            positions.put(trees, list_sr);
            return list_sr;
}

Visitor method: compute source positions for a list of nodes.

 public SourceRange cspCases(List<JCCase> trees) 
{
            if ((trees == null) || !(trees.nonEmpty())) return null;
            SourceRange list_sr = new SourceRange();
            for (List< JCCase > l = trees; l.nonEmpty(); l = l.tail) {
                list_sr.mergeWith(csp(l.head));
            }
            positions.put(trees, list_sr);
            return list_sr;
}

Visitor method: compute source positions for a list of case blocks of switch statements.

 public SourceRange cspCatchers(List<JCCatch> trees) 
{
            if ((trees == null) || !(trees.nonEmpty())) return null;
            SourceRange list_sr = new SourceRange();
            for (List< JCCatch > l = trees; l.nonEmpty(); l = l.tail) {
                list_sr.mergeWith(csp(l.head));
            }
            positions.put(trees, list_sr);
            return list_sr;
}

Visitor method: compute source positions for a list of catch clauses in try statements.

 public int endPos(JCTree tree) 
{
            if (tree == null) return Position.NOPOS;
            if (tree.getTag() == JCTree.BLOCK)
                return ((JCBlock) tree).endpos;
            Integer endpos = endPositions.get(tree);
            if (endpos != null)
                return endpos.intValue();
            return Position.NOPOS;
}

The end position of given tree, if it has defined endpos, NOPOS otherwise.

 public int startPos(JCTree tree) 
{
            if (tree == null) return Position.NOPOS;
            return tree.pos;
}

The start position of given tree.

 public  void visitApply(JCMethodInvocation tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.meth));
            sr.mergeWith(csp(tree.args));
            result = sr;
}

 public  void visitAssert(JCAssert tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.cond));
            sr.mergeWith(csp(tree.detail));
            result = sr;
}

 public  void visitAssign(JCAssign tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.lhs));
            sr.mergeWith(csp(tree.rhs));
            result = sr;
}

 public  void visitAssignop(JCAssignOp tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.lhs));
            sr.mergeWith(csp(tree.rhs));
            result = sr;
}

 public  void visitBinary(JCBinary tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.lhs));
            sr.mergeWith(csp(tree.rhs));
            result = sr;
}

 public  void visitBlock(JCBlock tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            csp(tree.stats);    // doesn't compare because block's ending position is defined
            result = sr;
}

 public  void visitBreak(JCBreak tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            result = sr;
}

 public  void visitCase(JCCase tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.pat));
            sr.mergeWith(csp(tree.stats));
            result = sr;
}

 public  void visitCatch(JCCatch tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.param));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitConditional(JCConditional tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.cond));
            sr.mergeWith(csp(tree.truepart));
            sr.mergeWith(csp(tree.falsepart));
            result = sr;
}

 public  void visitContinue(JCContinue tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            result = sr;
}

 public  void visitDoLoop(JCDoWhileLoop tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.body));
            sr.mergeWith(csp(tree.cond));
            result = sr;
}

 public  void visitErroneous(JCErroneous tree) 
{
            result = null;
}

 public  void visitExec(JCExpressionStatement tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.expr));
            result = sr;
}

 public  void visitForLoop(JCForLoop tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.init));
            sr.mergeWith(csp(tree.cond));
            sr.mergeWith(csp(tree.step));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitForeachLoop(JCEnhancedForLoop tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.var));
            sr.mergeWith(csp(tree.expr));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitIdent(JCIdent tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            result = sr;
}

 public  void visitIf(JCIf tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.cond));
            sr.mergeWith(csp(tree.thenpart));
            sr.mergeWith(csp(tree.elsepart));
            result = sr;
}

 public  void visitIndexed(JCArrayAccess tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.indexed));
            sr.mergeWith(csp(tree.index));
            result = sr;
}

 public  void visitLabelled(JCLabeledStatement tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitLiteral(JCLiteral tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            result = sr;
}

 public  void visitMethodDef(JCMethodDecl tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitNewArray(JCNewArray tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.elemtype));
            sr.mergeWith(csp(tree.dims));
            sr.mergeWith(csp(tree.elems));
            result = sr;
}

 public  void visitNewClass(JCNewClass tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.encl));
            sr.mergeWith(csp(tree.clazz));
            sr.mergeWith(csp(tree.args));
            sr.mergeWith(csp(tree.def));
            result = sr;
}

 public  void visitParens(JCParens tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.expr));
            result = sr;
}

 public  void visitReturn(JCReturn tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.expr));
            result = sr;
}

 public  void visitSelect(JCFieldAccess tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.selected));
            result = sr;
}

 public  void visitSkip(JCSkip tree) 
{
            // endPos is the same as startPos for the empty statement
            SourceRange sr = new SourceRange(startPos(tree), startPos(tree));
            result = sr;
}

 public  void visitSwitch(JCSwitch tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.selector));
            sr.mergeWith(cspCases(tree.cases));
            result = sr;
}

 public  void visitSynchronized(JCSynchronized tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.lock));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitThrow(JCThrow tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.expr));
            result = sr;
}

 public  void visitTree(JCTree tree) 
{
            Assert.error();
}

 public  void visitTry(JCTry tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.resources));
            sr.mergeWith(csp(tree.body));
            sr.mergeWith(cspCatchers(tree.catchers));
            sr.mergeWith(csp(tree.finalizer));
            result = sr;
}

 public  void visitTypeApply(JCTypeApply tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.clazz));
            sr.mergeWith(csp(tree.arguments));
            result = sr;
}

 public  void visitTypeArray(JCArrayTypeTree tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.elemtype));
            result = sr;
}

 public  void visitTypeCast(JCTypeCast tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.clazz));
            sr.mergeWith(csp(tree.expr));
            result = sr;
}

 public  void visitTypeIdent(JCPrimitiveTypeTree tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            result = sr;
}

 public  void visitTypeParameter(JCTypeParameter tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.bounds));
            result = sr;
}

 public  void visitTypeTest(JCInstanceOf tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.expr));
            sr.mergeWith(csp(tree.clazz));
            result = sr;
}

 public  void visitUnary(JCUnary tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.arg));
            result = sr;
}

 public  void visitVarDef(JCVariableDecl tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            csp(tree.vartype);
            sr.mergeWith(csp(tree.init));
            result = sr;
}

 public  void visitWhileLoop(JCWhileLoop tree) 
{
            SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
            sr.mergeWith(csp(tree.cond));
            sr.mergeWith(csp(tree.body));
            result = sr;
}

 public  void visitWildcard(JCWildcard tree) 
{
            result = null;
}