com.google.gwt.dev.js.JsniFieldAsMethodReferenceVisitor.java Source code

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Here is the source code for com.google.gwt.dev.js.JsniFieldAsMethodReferenceVisitor.java

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/*******************************************************************************
 * Copyright 2011 Google Inc. All Rights Reserved.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.google.gwt.dev.js;

import org.apache.commons.lang.StringUtils;

import com.google.gwt.dev.js.ast.JsArrayAccess;
import com.google.gwt.dev.js.ast.JsArrayLiteral;
import com.google.gwt.dev.js.ast.JsBinaryOperation;
import com.google.gwt.dev.js.ast.JsConditional;
import com.google.gwt.dev.js.ast.JsContext;
import com.google.gwt.dev.js.ast.JsExprStmt;
import com.google.gwt.dev.js.ast.JsExpression;
import com.google.gwt.dev.js.ast.JsFunction;
import com.google.gwt.dev.js.ast.JsInvocation;
import com.google.gwt.dev.js.ast.JsNameRef;
import com.google.gwt.dev.js.ast.JsNew;
import com.google.gwt.dev.js.ast.JsObjectLiteral;
import com.google.gwt.dev.js.ast.JsPostfixOperation;
import com.google.gwt.dev.js.ast.JsPrefixOperation;
import com.google.gwt.dev.js.ast.JsRegExp;
import com.google.gwt.dev.js.ast.JsVisitor;

/**
 * Determines if an expression statement needs to be surrounded by parentheses.
 * >>> XXX Instantiations
 * 
 * @author mitin_aa
 */
public class JsniFieldAsMethodReferenceVisitor extends JsVisitor {

    public static boolean exec(JsExprStmt statement) {
        JsniFieldAsMethodReferenceVisitor visitor = new JsniFieldAsMethodReferenceVisitor();
        JsExpression expression = statement.getExpression();
        // Pure function declarations do not need parentheses
        if (expression instanceof JsFunction) {
            return false;
        }
        visitor.accept(statement.getExpression());
        return visitor.needsParentheses;
    }

    private boolean needsParentheses = false;

    private JsniFieldAsMethodReferenceVisitor() {
    }

    public boolean visit(JsArrayAccess x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsArrayLiteral x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsBinaryOperation x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsConditional x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsFunction x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsInvocation x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsNameRef x, JsContext<JsExpression> ctx) {
        needsParentheses = isJsniFieldReference(x.getShortIdent());
        return false;
    }

    private boolean isJsniFieldReference(String name) {
        name = StringUtils.substringAfterLast(name, "@");
        if (!StringUtils.isEmpty(name) && name.indexOf("::") != -1) {
            return !name.endsWith(")");
        }
        return false;
    }

    public boolean visit(JsNew x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsObjectLiteral x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsPostfixOperation x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsPrefixOperation x, JsContext<JsExpression> ctx) {
        return false;
    }

    public boolean visit(JsRegExp x, JsContext<JsExpression> ctx) {
        return false;
    }

}