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1
11 package org.eclipse.jdt.internal.ui.text.correction;
12
13 import java.util.List  ;
14
15 import org.eclipse.jdt.core.ICompilationUnit;
16 import org.eclipse.jdt.core.dom.AST;
17 import org.eclipse.jdt.core.dom.ASTNode;
18 import org.eclipse.jdt.core.dom.Block;
19 import org.eclipse.jdt.core.dom.CompilationUnit;
20 import org.eclipse.jdt.core.dom.Expression;
21 import org.eclipse.jdt.core.dom.ExpressionStatement;
22 import org.eclipse.jdt.core.dom.IBinding;
23 import org.eclipse.jdt.core.dom.IMethodBinding;
24 import org.eclipse.jdt.core.dom.ITypeBinding;
25 import org.eclipse.jdt.core.dom.IVariableBinding;
26 import org.eclipse.jdt.core.dom.MethodDeclaration;
27 import org.eclipse.jdt.core.dom.Modifier;
28 import org.eclipse.jdt.core.dom.ReturnStatement;
29 import org.eclipse.jdt.core.dom.rewrite.ASTRewrite;
30
31 import org.eclipse.jdt.internal.corext.dom.ASTNodeFactory;
32 import org.eclipse.jdt.internal.corext.dom.ASTNodes;
33 import org.eclipse.jdt.internal.corext.dom.ScopeAnalyzer;
34
35 import org.eclipse.jdt.internal.ui.JavaPluginImages;
36
37 public class MissingReturnTypeCorrectionProposal extends LinkedCorrectionProposal {
38
39 private static final String RETURN_EXPRESSION_KEY= "value";
41 private MethodDeclaration fMethodDecl;
42 private ReturnStatement fExistingReturn;
43
44 public MissingReturnTypeCorrectionProposal(ICompilationUnit cu, MethodDeclaration decl, ReturnStatement existingReturn, int relevance) {
45 super("", cu, null, relevance, JavaPluginImages.get(JavaPluginImages.IMG_CORRECTION_CHANGE)); fMethodDecl= decl;
47 fExistingReturn= existingReturn;
48 }
49
50 public String getDisplayString() {
51 if (fExistingReturn != null) {
52 return CorrectionMessages.MissingReturnTypeCorrectionProposal_changereturnstatement_description;
53 } else {
54 return CorrectionMessages.MissingReturnTypeCorrectionProposal_addreturnstatement_description;
55 }
56 }
57
58
61 protected ASTRewrite getRewrite() {
62 AST ast= fMethodDecl.getAST();
63
64 ITypeBinding returnBinding= getReturnTypeBinding();
65
66 if (fExistingReturn != null) {
67 ASTRewrite rewrite= ASTRewrite.create(ast);
68
69 Expression expression= evaluateReturnExpressions(ast, returnBinding, fExistingReturn.getStartPosition());
70 if (expression != null) {
71 rewrite.set(fExistingReturn, ReturnStatement.EXPRESSION_PROPERTY, expression, null);
72
73 addLinkedPosition(rewrite.track(expression), true, RETURN_EXPRESSION_KEY);
74 }
75 return rewrite;
76 } else {
77 ASTRewrite rewrite= ASTRewrite.create(ast);
78
79 Block block= fMethodDecl.getBody();
80
81 List statements= block.statements();
82 int nStatements= statements.size();
83 ASTNode lastStatement= null;
84 if (nStatements > 0) {
85 lastStatement= (ASTNode) statements.get(nStatements - 1);
86 }
87
88 if (returnBinding != null && lastStatement instanceof ExpressionStatement && lastStatement.getNodeType() != ASTNode.ASSIGNMENT) {
89 Expression expression= ((ExpressionStatement) lastStatement).getExpression();
90 ITypeBinding binding= expression.resolveTypeBinding();
91 if (binding != null && binding.isAssignmentCompatible(returnBinding)) {
92 Expression placeHolder= (Expression) rewrite.createMoveTarget(expression);
93
94 ReturnStatement returnStatement= ast.newReturnStatement();
95 returnStatement.setExpression(placeHolder);
96
97 rewrite.replace(lastStatement, returnStatement, null);
98 return rewrite;
99 }
100 }
101
102 int offset;
103 if (lastStatement == null) {
104 offset= block.getStartPosition() + 1;
105 } else {
106 offset= lastStatement.getStartPosition() + lastStatement.getLength();
107 }
108 ReturnStatement returnStatement= ast.newReturnStatement();
109 Expression expression= evaluateReturnExpressions(ast, returnBinding, offset);
110
111 returnStatement.setExpression(expression);
112
113 rewrite.getListRewrite(block, Block.STATEMENTS_PROPERTY).insertLast(returnStatement, null);
114
115 addLinkedPosition(rewrite.track(returnStatement.getExpression()), true, RETURN_EXPRESSION_KEY);
116 return rewrite;
117 }
118 }
119
120 private ITypeBinding getReturnTypeBinding() {
121 IMethodBinding methodBinding= fMethodDecl.resolveBinding();
122 if (methodBinding != null && methodBinding.getReturnType() != null) {
123 return methodBinding.getReturnType();
124 }
125 return null;
126 }
127
128
129
132 private Expression evaluateReturnExpressions(AST ast, ITypeBinding returnBinding, int returnOffset) {
133 CompilationUnit root= (CompilationUnit) fMethodDecl.getRoot();
134
135 Expression result= null;
136 if (returnBinding != null) {
137 ScopeAnalyzer analyzer= new ScopeAnalyzer(root);
138 IBinding[] bindings= analyzer.getDeclarationsInScope(returnOffset, ScopeAnalyzer.VARIABLES | ScopeAnalyzer.CHECK_VISIBILITY );
139 for (int i= 0; i < bindings.length; i++) {
140 IVariableBinding curr= (IVariableBinding) bindings[i];
141 ITypeBinding type= curr.getType();
142 if (type != null && type.isAssignmentCompatible(returnBinding) && testModifier(curr)) {
143 if (result == null) {
144 result= ast.newSimpleName(curr.getName());
145 }
146 addLinkedPositionProposal(RETURN_EXPRESSION_KEY, curr.getName(), null);
147 }
148 }
149 }
150 Expression defaultExpression= ASTNodeFactory.newDefaultExpression(ast, fMethodDecl.getReturnType2(), fMethodDecl.getExtraDimensions());
151 addLinkedPositionProposal(RETURN_EXPRESSION_KEY, ASTNodes.asString(defaultExpression), null);
152 if (result == null) {
153 return defaultExpression;
154 }
155 return result;
156 }
157
158 private boolean testModifier(IVariableBinding curr) {
159 int modifiers= curr.getModifiers();
160 int staticFinal= Modifier.STATIC | Modifier.FINAL;
161 if ((modifiers & staticFinal) == staticFinal) {
162 return false;
163 }
164 if (Modifier.isStatic(modifiers) && !Modifier.isStatic(fMethodDecl.getModifiers())) {
165 return false;
166 }
167 return true;
168 }
169
170 }
171 |
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