com.puppycrawl.tools.checkstyle.checks.whitespace.NoLineWrapCheck Maven / Gradle / Ivy

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Checkstyle is a development tool to help programmers write Java code that adheres to a coding standard
There is a newer version: 10.18.1
////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2021 the original author or authors.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
////////////////////////////////////////////////////////////////////////////////

package com.puppycrawl.tools.checkstyle.checks.whitespace;

import com.puppycrawl.tools.checkstyle.StatelessCheck;
import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
import com.puppycrawl.tools.checkstyle.utils.TokenUtil;

/**
 * Checks that chosen statements are not line-wrapped.
 * By default this Check restricts wrapping import and package statements,
 * but it's possible to check any statement.
 * 
 * 
 * 
 * Property {@code tokens} - tokens to check
 * Type is {@code java.lang.String[]}.
 * Validation type is {@code tokenSet}.
 * Default value is:
 * 
 * PACKAGE_DEF,
 * 
 * IMPORT,
 * 
 * STATIC_IMPORT.
 * 
 * 
 * 
 * To configure the check to force no line-wrapping
 * in package and import statements (default values):
 * 
 *  * <module name="NoLineWrap"/>
 * 
 * Examples of line-wrapped statements (bad case):
 * 
 *  * package com.puppycrawl. // violation
 *     tools.checkstyle.checks;
 *
 * import com.puppycrawl.tools. // violation
 *     checkstyle.api.AbstractCheck;
 *
 * import static java.math. // violation
 *     BigInteger.ZERO;
 * 
 *
 * 
 * Examples:
 * 
 *  * package com.puppycrawl.tools.checkstyle. // violation
 *   checks.whitespace;
 *
 * import java.lang.Object; // OK
 * import java.lang. // violation
 *   Integer;
 *
 * import static java.math. // violation
 *   BigInteger.TEN;
 * 
 *  * package com.puppycrawl.tools.checkstyle.checks.coding; // OK
 *
 * import java.lang. // violation
 *   Boolean;
 *
 * import static java.math.BigInteger.ONE; // OK
 * 
 *
 * 
 * To configure the check to force no line-wrapping only
 * in import statements:
 * 
 *  * <module name="NoLineWrap">
 *   <property name="tokens" value="IMPORT"/>
 * </module>
 * 
 * 
 * Example:
 * 
 *  * package com.puppycrawl. // OK
 *   tools.checkstyle.checks;
 *
 * import java.io.*; // OK
 * import java.lang. // violation
 *  Boolean;
 *
 * import static java.math. // OK
 * BigInteger.ZERO;
 * 
 * 
 * To configure the check to force no line-wrapping only
 * in class, method and constructor definitions:
 * 
 *  * <module name="NoLineWrap">
 *   <property name="tokens" value="CLASS_DEF, METHOD_DEF, CTOR_DEF"/>
 * </module>
 * 
 * 
 * Example:
 * 
 *  * public class // violation, class definition not wrapped in a single line
 *   Foo {
 *
 *   public Foo() { // OK
 *   }
 *
 *   public static void // violation, method definition not wrapped in a single line
 *     doSomething() {
 *   }
 * }
 *
 * public class Bar { // OK
 *
 *   public // violation, constructor definition not wrapped in a single line
 *     Bar() {
 *   }
 *
 *   public int fun() { // OK
 *   }
 * }
 * 
 *
 * Examples of not line-wrapped statements (good case):
 * 
 *  * import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
 * import static java.math.BigInteger.ZERO;
 * 
 * 
 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
 * 
 * 
 * Violation Message Keys:
 * 
 * 
 * 
 * {@code no.line.wrap}
 * 
 * 
 *
 * @since 5.8
 */
@StatelessCheck
public class NoLineWrapCheck extends AbstractCheck {

    /**
     * A key is pointing to the warning message text in "messages.properties"
     * file.
     */
    public static final String MSG_KEY = "no.line.wrap";

    @Override
    public int[] getDefaultTokens() {
        return new int[] {TokenTypes.PACKAGE_DEF, TokenTypes.IMPORT, TokenTypes.STATIC_IMPORT};
    }

    @Override
    public int[] getAcceptableTokens() {
        return new int[] {
            TokenTypes.IMPORT,
            TokenTypes.STATIC_IMPORT,
            TokenTypes.PACKAGE_DEF,
            TokenTypes.CLASS_DEF,
            TokenTypes.METHOD_DEF,
            TokenTypes.CTOR_DEF,
            TokenTypes.ENUM_DEF,
            TokenTypes.INTERFACE_DEF,
            TokenTypes.RECORD_DEF,
            TokenTypes.COMPACT_CTOR_DEF,
        };
    }

    @Override
    public int[] getRequiredTokens() {
        return CommonUtil.EMPTY_INT_ARRAY;
    }

    @Override
    public void visitToken(DetailAST ast) {
        if (!TokenUtil.areOnSameLine(ast, ast.getLastChild())) {
            log(ast, MSG_KEY, ast.getText());
        }
    }

}