1 /***
2 * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
3 */
4 package net.sourceforge.pmd.rules.optimization;
5
6 import net.sourceforge.pmd.RuleContext;
7 import net.sourceforge.pmd.ast.ASTClassOrInterfaceDeclaration;
8 import net.sourceforge.pmd.ast.ASTFormalParameter;
9 import net.sourceforge.pmd.ast.ASTMethodDeclaration;
10 import net.sourceforge.pmd.symboltable.NameOccurrence;
11 import net.sourceforge.pmd.symboltable.Scope;
12 import net.sourceforge.pmd.symboltable.VariableNameDeclaration;
13
14 import java.text.MessageFormat;
15 import java.util.Iterator;
16 import java.util.List;
17 import java.util.Map;
18
19 public class MethodArgumentCouldBeFinal extends AbstractOptimizationRule {
20
21 public Object visit(ASTClassOrInterfaceDeclaration node, Object data) {
22 if (node.isInterface()) {
23 return data;
24 }
25 return super.visit(node, data);
26 }
27
28 public Object visit(ASTMethodDeclaration meth, Object data) {
29 if (meth.isNative() || meth.isAbstract()) {
30 return data;
31 }
32 Scope s = meth.getScope();
33 Map decls = s.getVariableDeclarations();
34 for (Iterator i = decls.keySet().iterator(); i.hasNext();) {
35 VariableNameDeclaration var = (VariableNameDeclaration)i.next();
36 if (!var.getAccessNodeParent().isFinal() && (var.getAccessNodeParent() instanceof ASTFormalParameter)) {
37 if (!assigned((List)decls.get(var))) {
38 RuleContext ctx = (RuleContext)data;
39 ctx.getReport().addRuleViolation(createRuleViolation(ctx, var.getAccessNodeParent(), MessageFormat.format(getMessage(), new Object[]{var.getImage()})));
40 }
41 }
42 }
43 return data;
44 }
45
46 private boolean assigned(List usages) {
47 for (Iterator j = usages.iterator(); j.hasNext();) {
48 NameOccurrence occ = (NameOccurrence) j.next();
49 if (occ.isOnLeftHandSide()) {
50 return true;
51 }
52 continue;
53 }
54 return false;
55 }
56 }