Examples with JCFieldAccess com.sun.tools.javac.tree.JCTree.JCFieldAccess used on opensource projects

Example 21 with JCFieldAccess

use of com.sun.tools.javac.tree.JCTree.JCFieldAccess in project error-prone by google.

the class ASTHelpers method sameVariable.

/**
   * Determines whether two expressions refer to the same variable. Note that returning false
   * doesn't necessarily mean the expressions do *not* refer to the same field. We don't attempt
   * to do any complex analysis here, just catch the obvious cases.
   */
public static boolean sameVariable(ExpressionTree expr1, ExpressionTree expr2) {
    // Throw up our hands if we're not comparing identifiers and/or field accesses.
    if ((expr1.getKind() != Kind.IDENTIFIER && expr1.getKind() != Kind.MEMBER_SELECT) || (expr2.getKind() != Kind.IDENTIFIER && expr2.getKind() != Kind.MEMBER_SELECT)) {
        return false;
    }
    Symbol sym1 = getSymbol(expr1);
    Symbol sym2 = getSymbol(expr2);
    if (sym1 == null) {
        throw new IllegalStateException("Couldn't get symbol for " + expr1);
    } else if (sym2 == null) {
        throw new IllegalStateException("Couldn't get symbol for " + expr2);
    }
    if (expr1.getKind() == Kind.IDENTIFIER && expr2.getKind() == Kind.IDENTIFIER) {
        // foo == foo?
        return sym1.equals(sym2);
    } else if (expr1.getKind() == Kind.MEMBER_SELECT && expr2.getKind() == Kind.MEMBER_SELECT) {
        // foo.baz.bar == foo.baz.bar?
        return sym1.equals(sym2) && sameVariable(((JCFieldAccess) expr1).selected, ((JCFieldAccess) expr2).selected);
    } else {
        // this.foo == foo?
        ExpressionTree selected = null;
        if (expr1.getKind() == Kind.IDENTIFIER) {
            selected = ((JCFieldAccess) expr2).selected;
        } else {
            selected = ((JCFieldAccess) expr1).selected;
        }
        // TODO(eaftan): really shouldn't be relying on .toString()
        return selected.toString().equals("this") && sym1.equals(sym2);
    }
}

Example 22 with JCFieldAccess

use of com.sun.tools.javac.tree.JCTree.JCFieldAccess in project error-prone by google.

the class Matchers method receiverSameAsArgument.

/**
   * Matches when the receiver of an instance method is the same reference as a particular argument to the method.
   * For example, receiverSameAsArgument(1) would match {@code obj.method("", obj)}
   *
   * @param argNum The number of the argument to compare against (zero-based.
   */
public static Matcher<? super MethodInvocationTree> receiverSameAsArgument(final int argNum) {
    return new Matcher<MethodInvocationTree>() {

        @Override
        public boolean matches(MethodInvocationTree t, VisitorState state) {
            List<? extends ExpressionTree> args = t.getArguments();
            if (args.size() <= argNum) {
                return false;
            }
            ExpressionTree arg = args.get(argNum);
            JCExpression methodSelect = (JCExpression) t.getMethodSelect();
            if (methodSelect instanceof JCFieldAccess) {
                JCFieldAccess fieldAccess = (JCFieldAccess) methodSelect;
                return ASTHelpers.sameVariable(fieldAccess.getExpression(), arg);
            } else if (methodSelect instanceof JCIdent) {
                // A bare method call: "equals(foo)".  Receiver is implicitly "this".
                return "this".equals(arg.toString());
            }
            return false;
        }
    };
}

Example 23 with JCFieldAccess

use of com.sun.tools.javac.tree.JCTree.JCFieldAccess in project error-prone by google.

the class SelfAssignment method describeForAssignment.

/**
   * We expect that the lhs is a field and the rhs is an identifier, specifically
   * a parameter to the method.  We base our suggested fixes on this expectation.
   *
   * Case 1: If lhs is a field and rhs is an identifier, find a method parameter
   * of the same type and similar name and suggest it as the rhs.  (Guess that they
   * have misspelled the identifier.)
   *
   * Case 2: If lhs is a field and rhs is not an identifier, find a method parameter
   * of the same type and similar name and suggest it as the rhs.
   *
   * Case 3: If lhs is not a field and rhs is an identifier, find a class field
   * of the same type and similar name and suggest it as the lhs.
   *
   * Case 4: Otherwise suggest deleting the assignment.
   */
public Description describeForAssignment(AssignmentTree assignmentTree, VisitorState state) {
    // the statement that is the parent of the self-assignment expression
    Tree parent = state.getPath().getParentPath().getLeaf();
    // default fix is to delete assignment
    Fix fix = SuggestedFix.delete(parent);
    ExpressionTree lhs = assignmentTree.getVariable();
    ExpressionTree rhs = assignmentTree.getExpression();
    // if this is a method invocation, they must be calling checkNotNull()
    if (assignmentTree.getExpression().getKind() == METHOD_INVOCATION) {
        // change the default fix to be "checkNotNull(x)" instead of "x = checkNotNull(x)"
        fix = SuggestedFix.replace(assignmentTree, rhs.toString());
        // new rhs is first argument to checkNotNull()
        rhs = stripCheckNotNull(rhs, state);
    }
    if (lhs.getKind() == MEMBER_SELECT) {
        // rhs should be either identifier or field access
        assert (rhs.getKind() == IDENTIFIER || rhs.getKind() == MEMBER_SELECT);
        // get current name of rhs
        String rhsName = null;
        if (rhs.getKind() == IDENTIFIER) {
            rhsName = ((JCIdent) rhs).name.toString();
        } else if (rhs.getKind() == MEMBER_SELECT) {
            rhsName = ((JCFieldAccess) rhs).name.toString();
        }
        // find method parameters of the same type
        Type type = ((JCFieldAccess) lhs).type;
        TreePath path = state.getPath();
        while (path != null && path.getLeaf().getKind() != METHOD) {
            path = path.getParentPath();
        }
        JCMethodDecl method = (JCMethodDecl) path.getLeaf();
        int minEditDistance = Integer.MAX_VALUE;
        String replacement = null;
        for (JCVariableDecl var : method.params) {
            if (var.type == type) {
                int editDistance = EditDistance.getEditDistance(rhsName, var.name.toString());
                if (editDistance < minEditDistance) {
                    // pick one with minimum edit distance
                    minEditDistance = editDistance;
                    replacement = var.name.toString();
                }
            }
        }
        if (replacement != null) {
            // suggest replacing rhs with the parameter
            fix = SuggestedFix.replace(rhs, replacement);
        }
    } else if (rhs.getKind() == IDENTIFIER) {
        // lhs should be identifier
        assert (lhs.getKind() == IDENTIFIER);
        // get current name of lhs
        String lhsName = ((JCIdent) rhs).name.toString();
        // find class instance fields of the same type
        Type type = ((JCIdent) lhs).type;
        TreePath path = state.getPath();
        while (path != null && !(path.getLeaf() instanceof JCClassDecl)) {
            path = path.getParentPath();
        }
        if (path == null) {
            throw new IllegalStateException("Expected to find an enclosing class declaration");
        }
        JCClassDecl klass = (JCClassDecl) path.getLeaf();
        int minEditDistance = Integer.MAX_VALUE;
        String replacement = null;
        for (JCTree member : klass.getMembers()) {
            if (member.getKind() == VARIABLE) {
                JCVariableDecl var = (JCVariableDecl) member;
                if (!Flags.isStatic(var.sym) && var.type == type) {
                    int editDistance = EditDistance.getEditDistance(lhsName, var.name.toString());
                    if (editDistance < minEditDistance) {
                        // pick one with minimum edit distance
                        minEditDistance = editDistance;
                        replacement = var.name.toString();
                    }
                }
            }
        }
        if (replacement != null) {
            // suggest replacing lhs with the field
            fix = SuggestedFix.replace(lhs, "this." + replacement);
        }
    }
    return describeMatch(assignmentTree, fix);
}

Example 24 with JCFieldAccess

use of com.sun.tools.javac.tree.JCTree.JCFieldAccess in project error-prone by google.

the class ProtoFieldNullComparison method getMethodName.

private static String getMethodName(ExpressionTree tree) {
    MethodInvocationTree method = (MethodInvocationTree) tree;
    ExpressionTree expressionTree = method.getMethodSelect();
    JCFieldAccess access = (JCFieldAccess) expressionTree;
    return access.sym.getQualifiedName().toString();
}

Example 25 with JCFieldAccess

use of com.sun.tools.javac.tree.JCTree.JCFieldAccess in project error-prone by google.

the class ProtoFieldPreconditionsCheckNotNull method isGetMethodInvocation.

private static boolean isGetMethodInvocation(ExpressionTree tree, VisitorState state) {
    if (tree.getKind() == Tree.Kind.METHOD_INVOCATION) {
        MethodInvocationTree method = (MethodInvocationTree) tree;
        if (!method.getArguments().isEmpty()) {
            return false;
        }
        if (returnsListMatcher.matches(method, state)) {
            return false;
        }
        ExpressionTree expressionTree = method.getMethodSelect();
        if (expressionTree instanceof JCFieldAccess) {
            JCFieldAccess access = (JCFieldAccess) expressionTree;
            String methodName = access.sym.getQualifiedName().toString();
            return isFieldGetMethod(methodName);
        }
        return true;
    }
    return false;
}