com.sun.source.tree.MethodTree#getThrows ( )源码实例Demo

public Void visitMethod(MethodTree node, Object p) {
    super.visitMethod(node, p);
    Element al = model.getElement(node);
    if ("foo()".equals(al.toString())) {
        List<ExpressionTree> l = new ArrayList<ExpressionTree>();
        int i=0;
        for (ExpressionTree n: node.getThrows()) {
            if (i!=index) {
                l.add(n);
            }
        }
        MethodTree njuMethod = make.Method(
                node.getModifiers(),
                node.getName(),
                (ExpressionTree) node.getReturnType(),
                node.getTypeParameters(),
                node.getParameters(),
                l,
                node.getBody(),
                (ExpressionTree) node.getDefaultValue()
                );
        model.setElement(njuMethod, al);
        copy.rewrite(node, njuMethod);
    }
    return null;
}
 

private static boolean isInHeader(CompilationInfo info, MethodTree tree, int offset) {
    CompilationUnitTree cut = info.getCompilationUnit();
    SourcePositions sp = info.getTrees().getSourcePositions();
    long lastKnownOffsetInHeader = sp.getStartPosition(cut, tree);
    
    List<? extends ExpressionTree> throwz;
    List<? extends VariableTree> params;
    List<? extends TypeParameterTree> typeparams;
    
    if ((throwz = tree.getThrows()) != null && !throwz.isEmpty()) {
        lastKnownOffsetInHeader = sp.getEndPosition(cut, throwz.get(throwz.size() - 1));
    } else if ((params = tree.getParameters()) != null && !params.isEmpty()) {
        lastKnownOffsetInHeader = sp.getEndPosition(cut, params.get(params.size() - 1));
    } else if ((typeparams = tree.getTypeParameters()) != null && !typeparams.isEmpty()) {
        lastKnownOffsetInHeader = sp.getEndPosition(cut, typeparams.get(typeparams.size() - 1));
    } else if (tree.getReturnType() != null) {
        lastKnownOffsetInHeader = sp.getEndPosition(cut, tree.getReturnType());
    } else if (tree.getModifiers() != null) {
        lastKnownOffsetInHeader = sp.getEndPosition(cut, tree.getModifiers());
    }
    
    TokenSequence<JavaTokenId> ts = info.getTreeUtilities().tokensFor(tree);
    
    ts.move((int) lastKnownOffsetInHeader);
    
    while (ts.moveNext()) {
        if (ts.token().id() == JavaTokenId.LBRACE || ts.token().id() == JavaTokenId.SEMICOLON) {
            return offset < ts.offset();
        }
    }
    
    return false;
}
 

private static List<? extends TypeMirror> computeMethod(Set<ElementKind> types, CompilationInfo info, TreePath parent, TypeMirror[] typeParameterBound, Tree error, int offset) {
       //class or field:
       //check the error is in the body:
       //#92419: check for abstract method/method without body:
       MethodTree mt = (MethodTree) parent.getLeaf();
       
       if (mt.getReturnType() == error) {
           types.add(ElementKind.CLASS);
           types.add(ElementKind.INTERFACE);
           types.add(ElementKind.ENUM);
       }

       List<? extends ExpressionTree> throwList = mt.getThrows();
if (throwList != null && !throwList.isEmpty()) {
           for (ExpressionTree t : throwList) {
               if (t == error) {
                   types.add(ElementKind.CLASS);
                   typeParameterBound[0] = info.getElements().getTypeElement("java.lang.Exception").asType();
                   break;
               }
           }
}
       
       if (mt.getBody() == null) {
           return null;
       }
       
       try {
           Document doc = info.getDocument();
           
           if (doc != null) {//XXX
               int bodyStart = findBodyStart(parent.getLeaf(), info.getCompilationUnit(), info.getTrees().getSourcePositions(), doc);
               int bodyEnd   = (int) info.getTrees().getSourcePositions().getEndPosition(info.getCompilationUnit(), parent.getLeaf());

               types.add(ElementKind.PARAMETER);
               types.add(ElementKind.LOCAL_VARIABLE);
               types.add(ElementKind.FIELD);

               if (bodyStart <= offset && offset <= bodyEnd)
                   return Collections.singletonList(info.getElements().getTypeElement("java.lang.Object").asType());
           }
       } catch (IOException ex) {
           Logger.getLogger("global").log(Level.INFO, ex.getMessage(), ex);
       }
       
       return null;
   }
 

private static List<? extends TypeMirror> computeMethod(Set<ElementKind> types, CompilationInfo info, TreePath parent, TypeMirror[] typeParameterBound, Tree error, int offset) {
       //class or field:
       //check the error is in the body:
       //#92419: check for abstract method/method without body:
       MethodTree mt = (MethodTree) parent.getLeaf();
       
       if (mt.getReturnType() == error) {
           types.add(ElementKind.CLASS);
           types.add(ElementKind.INTERFACE);
           types.add(ElementKind.ENUM);
       }

       List<? extends ExpressionTree> throwList = mt.getThrows();
if (throwList != null && !throwList.isEmpty()) {
           for (ExpressionTree t : throwList) {
               if (t == error) {
                   types.add(ElementKind.CLASS);
                   TypeElement tel = info.getElements().getTypeElement("java.lang.Exception");
                   if (tel == null) {
                       return null;
                   }
                   typeParameterBound[0] = tel.asType();
                   break;
               }
           }
}
       
       if (mt.getBody() == null) {
           return null;
       }
       
       try {
           Document doc = info.getDocument();
           
           if (doc != null) {//XXX
               int bodyStart = Utilities.findBodyStart(info, parent.getLeaf(), info.getCompilationUnit(), info.getTrees().getSourcePositions(), doc);
               int bodyEnd   = (int) info.getTrees().getSourcePositions().getEndPosition(info.getCompilationUnit(), parent.getLeaf());

               types.add(ElementKind.PARAMETER);
               types.add(ElementKind.LOCAL_VARIABLE);
               types.add(ElementKind.FIELD);

               if (bodyStart <= offset && offset <= bodyEnd) {
                   return typeMirrorCollection(info, "java.lang.Object");
               }
           }
       } catch (IOException ex) {
           Logger.getLogger("global").log(Level.INFO, ex.getMessage(), ex);
       }
       
       return null;
   }
 

/**
 * Computes possible types for throw expression. Throw can safely throw an exception, which is
 * either declared by method as a thrown type, or catched within method, by an upper try-catch block.
 * Unchecked exceptions are permitted (derivatives of RuntimeException or Error).
 */
@Override
public List<? extends TypeMirror> visitThrow(ThrowTree node, Object p) {
    List<TypeMirror> result = new ArrayList<TypeMirror>();
    TreePath parents = getCurrentPath();
    Tree prev = null;
    while (parents != null && parents.getLeaf().getKind() != Tree.Kind.METHOD) {
        Tree l = parents.getLeaf();
        if (l.getKind() == Tree.Kind.TRY) {
            TryTree tt = (TryTree) l;
            if (prev == tt.getBlock()) {
                for (CatchTree ct : tt.getCatches()) {
                    TypeMirror ex = info.getTrees().getTypeMirror(new TreePath(getCurrentPath(), ct.getParameter().getType()));
                    if (ex != null) {
                        switch (ex.getKind()) {
                            case DECLARED:
                                if (!result.contains(ex)) {
                                    result.add(ex);
                                }
                                break;
                            case UNION:
                                for (TypeMirror t : ((UnionType) ex).getAlternatives()) {
                                    if (!result.contains(t)) {
                                        result.add(t);
                                    }
                                }
                                break;
                        }
                    }
                }
            }
        }
        prev = l;
        parents = parents.getParentPath();
    }
    if (parents != null) {
        MethodTree mt = (MethodTree) parents.getLeaf();
        for (ExpressionTree etree : mt.getThrows()) {
            TypeMirror m = info.getTrees().getTypeMirror(new TreePath(parents, etree));
            if (m != null && !result.contains(m)) {
                result.add(m);
            }
        }
    }
    TypeMirror jlre = info.getElements().getTypeElement("java.lang.RuntimeException").asType(); // NOI18N
    TypeMirror jler = info.getElements().getTypeElement("java.lang.Error").asType(); // NOI18N
    for (TypeMirror em : result) {
        if (jlre != null && info.getTypes().isAssignable(jlre, em)) {
            jlre = null;
        }
        if (jler != null && info.getTypes().isAssignable(jler, em)) {
            jler = null;
        }
        if (jlre == null && jler == null) {
            break;
        }
    }
    if (jlre != null) {
        result.add(jlre);
    }
    if (jler != null) {
        result.add(jler);
    }
    return result;
}