1
2
3
4 package net.sourceforge.pmd.lang.java.rule.design;
5
6 import java.util.List;
7 import java.util.Map;
8
9 import net.sourceforge.pmd.RuleContext;
10 import net.sourceforge.pmd.lang.ast.Node;
11 import net.sourceforge.pmd.lang.java.ast.ASTAllocationExpression;
12 import net.sourceforge.pmd.lang.java.ast.ASTArgumentList;
13 import net.sourceforge.pmd.lang.java.ast.ASTCastExpression;
14 import net.sourceforge.pmd.lang.java.ast.ASTCatchStatement;
15 import net.sourceforge.pmd.lang.java.ast.ASTClassOrInterfaceType;
16 import net.sourceforge.pmd.lang.java.ast.ASTName;
17 import net.sourceforge.pmd.lang.java.ast.ASTPrimaryExpression;
18 import net.sourceforge.pmd.lang.java.ast.ASTPrimaryPrefix;
19 import net.sourceforge.pmd.lang.java.ast.ASTThrowStatement;
20 import net.sourceforge.pmd.lang.java.ast.ASTVariableDeclarator;
21 import net.sourceforge.pmd.lang.java.ast.ASTVariableDeclaratorId;
22 import net.sourceforge.pmd.lang.java.rule.AbstractJavaRule;
23 import net.sourceforge.pmd.lang.java.symboltable.NameOccurrence;
24 import net.sourceforge.pmd.lang.java.symboltable.VariableNameDeclaration;
25
26 import org.jaxen.JaxenException;
27
28
29
30
31
32
33
34 public class PreserveStackTraceRule extends AbstractJavaRule {
35
36
37
38 private static final String FIND_THROWABLE_INSTANCE =
39 "./VariableInitializer/Expression/PrimaryExpression/PrimaryPrefix/AllocationExpression" +
40 "[ClassOrInterfaceType[contains(@Image,'Exception')] and Arguments[count(*)=0]]";
41
42 private static final String FILL_IN_STACKTRACE = ".fillInStackTrace";
43
44 @Override
45 public Object visit(ASTCatchStatement catchStmt, Object data) {
46 String target = catchStmt.jjtGetChild(0).findChildrenOfType(ASTVariableDeclaratorId.class).get(0).getImage();
47
48 List<ASTThrowStatement> lstThrowStatements = catchStmt.findDescendantsOfType(ASTThrowStatement.class);
49 for (ASTThrowStatement throwStatement : lstThrowStatements) {
50 Node n = throwStatement.jjtGetChild(0).jjtGetChild(0);
51 if (n instanceof ASTCastExpression) {
52 ASTPrimaryExpression expr = (ASTPrimaryExpression) n.jjtGetChild(1);
53 if (expr.jjtGetNumChildren() > 1 && expr.jjtGetChild(1) instanceof ASTPrimaryPrefix) {
54 RuleContext ctx = (RuleContext) data;
55 addViolation(ctx, throwStatement);
56 }
57 continue;
58 }
59
60 ASTArgumentList args = throwStatement.getFirstDescendantOfType(ASTArgumentList.class);
61 if (args != null) {
62 Node parent = args.jjtGetParent().jjtGetParent();
63 if (parent instanceof ASTAllocationExpression) {
64
65 ck(data, target, throwStatement, parent);
66 } else {
67 ck(data, target, throwStatement, args);
68 }
69 }
70 else {
71 Node child = throwStatement.jjtGetChild(0);
72 while (child != null && child.jjtGetNumChildren() > 0
73 && !(child instanceof ASTName)) {
74 child = child.jjtGetChild(0);
75 }
76 if (child != null){
77 if ((child instanceof ASTName) && !target.equals(child.getImage()) && !child.hasImageEqualTo(target + FILL_IN_STACKTRACE)) {
78 Map<VariableNameDeclaration, List<NameOccurrence>> vars = ((ASTName) child).getScope().getVariableDeclarations();
79 for (Map.Entry<VariableNameDeclaration, List<NameOccurrence>> entry : vars.entrySet()) {
80 VariableNameDeclaration decl = entry.getKey();
81 List<NameOccurrence> occurrences = entry.getValue();
82 if (decl.getImage().equals(child.getImage())) {
83 if (!isInitCauseCalled(target, occurrences)) {
84 args = decl.getNode().jjtGetParent()
85 .getFirstDescendantOfType(ASTArgumentList.class);
86 if (args != null) {
87 ck(data, target, throwStatement, args);
88 }
89 }
90 }
91 }
92 } else if (child instanceof ASTClassOrInterfaceType){
93 addViolation(data, throwStatement);
94 }
95 }
96 }
97 }
98 return super.visit(catchStmt, data);
99 }
100
101 private boolean isInitCauseCalled(String target, List<NameOccurrence> occurrences) {
102 boolean initCauseCalled = false;
103 for (NameOccurrence occurrence : occurrences) {
104 String image = null;
105 if (occurrence.getLocation() != null) {
106 image = occurrence.getLocation().getImage();
107 }
108 if (image != null && image.endsWith("initCause")) {
109 ASTPrimaryExpression primaryExpression = occurrence.getLocation().getFirstParentOfType(ASTPrimaryExpression.class);
110 if (primaryExpression != null) {
111 ASTArgumentList args2 = primaryExpression.getFirstDescendantOfType(ASTArgumentList.class);
112 if (checkForTargetUsage(target, args2)) {
113 initCauseCalled = true;
114 break;
115 }
116 }
117 }
118 }
119 return initCauseCalled;
120 }
121
122 @Override
123 public Object visit(ASTVariableDeclarator node, Object data) {
124
125 try {
126 if (node.hasDescendantMatchingXPath(FIND_THROWABLE_INSTANCE)) {
127 String variableName = node.jjtGetChild(0).getImage();
128 ASTCatchStatement catchStmt = node.getFirstParentOfType(ASTCatchStatement.class);
129
130 while (catchStmt != null) {
131 List<Node> violations = catchStmt.findChildNodesWithXPath("//Expression/PrimaryExpression/PrimaryPrefix/Name[@Image = '" + variableName + "']");
132 if (!violations.isEmpty()) {
133
134
135 if (!useInitCause(violations.get(0), catchStmt)) {
136 addViolation(data, node);
137 }
138 }
139
140
141 catchStmt = catchStmt.getFirstParentOfType(ASTCatchStatement.class);
142 }
143 }
144 return super.visit(node, data);
145 } catch (JaxenException e) {
146
147 throw new IllegalStateException(e);
148 }
149 }
150
151 private boolean useInitCause(Node node, ASTCatchStatement catchStmt) {
152
153 if ( node != null && node.getImage() != null )
154 {
155 return catchStmt.hasDescendantMatchingXPath("./Block/BlockStatement/Statement/StatementExpression/PrimaryExpression/PrimaryPrefix/Name[@Image = '" + node.getImage() + ".initCause']");
156 }
157 return false;
158 }
159
160
161
162
163
164
165
166 private boolean checkForTargetUsage(String target, Node baseNode) {
167 boolean match = false;
168 if (target != null && baseNode != null) {
169 List<ASTName> nameNodes = baseNode.findDescendantsOfType(ASTName.class);
170 for (ASTName nameNode : nameNodes) {
171 if (target.equals(nameNode.getImage())) {
172 match = true;
173 break;
174 }
175 }
176 }
177 return match;
178 }
179
180 private void ck(Object data, String target, ASTThrowStatement throwStatement,
181 Node baseNode) {
182 if (!checkForTargetUsage(target, baseNode)) {
183 RuleContext ctx = (RuleContext) data;
184 addViolation(ctx, throwStatement);
185 }
186 }
187 }