Java Code Examples for com.puppycrawl.tools.checkstyle.api.DetailAST#getChildCount()

/**
 * Checks whether the given constructor seems to be a valid one or not.
 *
 * @param constructor
 *            The constructor in question.
 *
 * @return true if and only if the constructor seems to be valid.
 */
private static boolean isValidConstructor(final DetailAST constructor) {
	// Find the available parameters of the constructor
	final DetailAST parameters = constructor.findFirstToken(TokenTypes.PARAMETERS);

	// Make sure that there is exactly ONE parameter
	if (parameters.getChildCount() == 1) {
		final DetailAST fstParType = parameters.getFirstChild().findFirstToken(TokenTypes.TYPE);
		final DetailAST fstParArr = fstParType.findFirstToken(TokenTypes.ARRAY_DECLARATOR);
		if (fstParArr != null) {
			final DetailAST fstParIdent = fstParArr.findFirstToken(TokenTypes.IDENT);
			return fstParIdent.getText().equals(CONSTRUCTOR_PARAMETER);
		}
	}

	return false;
}
 

/**
 * This method finds out whether the given class implements the record factory
 * or not.
 *
 * @param clazz
 *            The class in question.
 *
 * @return true if and only if the class implements the record factory.
 */
private static boolean implementsFactory(final DetailAST clazz) {
	final DetailAST implementsClause = clazz.findFirstToken(TokenTypes.IMPLEMENTS_CLAUSE);
	if (implementsClause != null) {
		DetailAST clause = implementsClause.getFirstChild();

		// Run through the whole implements clause
		while (clause != null) {
			// It has to be a combination of two names
			if ((clause.getType() == TokenTypes.DOT) && (clause.getChildCount() == 2)) {
				final String fstClauseIdent = clause.getFirstChild().getText();
				final String sndClauseIdent = clause.getLastChild().getText();

				return (FACTORY_FST_NAME.equals(fstClauseIdent)) && (FACTORY_SND_NAME.equals(sndClauseIdent));
			}

			clause = clause.getNextSibling();
		}
	}
	return false;
}
 

/**
 * Checks whether the given constructor seems to be a valid one or not.
 *
 * @param constructor
 *            The constructor in question.
 *
 * @return true if and only if the constructor seems to be valid.
 */
private static boolean isValidConstructor(final DetailAST constructor) {
	// Find the available parameters of the constructor
	final DetailAST parameters = constructor.findFirstToken(TokenTypes.PARAMETERS);

	// Make sure that there are exactly TWO parameters (two parameters plus
	// a comma in the middle)
	if (parameters.getChildCount() == 3) {
		final DetailAST fstParType = parameters.getFirstChild().findFirstToken(TokenTypes.TYPE);
		final DetailAST sndParType = parameters.getLastChild().findFirstToken(TokenTypes.TYPE);

		final DetailAST fstParIdent = fstParType.findFirstToken(TokenTypes.IDENT);
		final DetailAST sndParIdent = sndParType.findFirstToken(TokenTypes.IDENT);

		return fstParIdent.getText().equals(CONSTRUCTOR_FST_PARAMETER)
				&& sndParIdent.getText().equals(CONSTRUCTOR_SND_PARAMETER);
	}

	return false;
}
 

private int countDescendantsOfType(DetailAST ast, int... types) {
	int count = 0;
	for (int type : types) {
		count += ast.getChildCount(type);
	}
	DetailAST child = ast.getFirstChild();
	while (child != null) {
		count += countDescendantsOfType(child, types);
		child = child.getNextSibling();
	}
	return count;
}
 

private boolean requiresParens(DetailAST expression) {
	if (expression != null && expression.getChildCount() > 1) {
		switch (expression.getType()) {
		case TokenTypes.METHOD_CALL:
		case TokenTypes.DOT:
			return false;
		}
		return true;
	}
	return false;
}
 

private boolean isSimpleEqualsExpression(DetailAST expression) {
	if (expression == null || expression.getType() != TokenTypes.EQUAL) {
		return false;
	}
	DetailAST child = expression.getFirstChild();
	while (child != null) {
		if (child.getChildCount() > 0) {
			return false;
		}
		child = child.getNextSibling();
	}
	return true;
}
 

private boolean isOrderedMethod(DetailAST ident, DetailAST parameters) {
	if ("equals".equals(ident.getText()) && parameters.getChildCount() == 1) {
		return true;
	}
	if ("hashCode".equals(ident.getText()) && parameters.getChildCount() == 0) {
		return true;
	}
	if ("toString".equals(ident.getText()) && parameters.getChildCount() == 0) {
		return true;
	}
	return false;
}
 

@Override
public void visitToken(DetailAST ast) {
  // find the OBJBLOCK node below the CLASS_DEF/INTERFACE_DEF
  DetailAST objBlock = ast.findFirstToken(TokenTypes.OBJBLOCK);
  // count the number of direct children of the OBJBLOCK
  // that are METHOD_DEFS
  int methodDefs = objBlock.getChildCount(TokenTypes.METHOD_DEF);
  // report error if limit is reached
  if (methodDefs > max) {
    log(ast.getLineNo(), "methodlimit", max);
  }
}
 

private boolean hasSingleParameter(DetailAST lambda) {
	DetailAST parameters = lambda.findFirstToken(TokenTypes.PARAMETERS);
	return (parameters == null) || (parameters.getChildCount(TokenTypes.PARAMETER_DEF) == 1);
}
 

/**
 * Checks if a given method is writeObject().
 * @param aAST method def to check
 * @return true if this is a writeObject() definition
 */
private boolean isWriteObject(DetailAST aAST)
{
    // name is writeObject...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"writeObject".equals(ident.getText())) {
        return false;
    }

    // returns void...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.LITERAL_VOID) {
        return false;
    }

    // should have one parameter...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params == null || params.getChildCount() != 1) {
        return false;
    }
    // and paramter's type should be java.io.ObjectOutputStream
    final DetailAST type =
        (DetailAST) ((DetailAST) params.getFirstChild())
            .findFirstToken(TokenTypes.TYPE).getFirstChild();
    final String typeName = FullIdent.createFullIdent(type).getText();
    if (!"java.io.ObjectOutputStream".equals(typeName)
        && !"ObjectOutputStream".equals(typeName))
    {
        return false;
    }

    // and, finally, it should throws java.io.IOException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 1) {
        return false;
    }
    final DetailAST expt = (DetailAST) throwsAST.getFirstChild();
    final String exceptionName = FullIdent.createFullIdent(expt).getText();
    if (!"java.io.IOException".equals(exceptionName)
        && !"IOException".equals(exceptionName))
    {
        return false;
    }

    return true;
}
 

/**
 * Checks if a given method is readObject().
 * @param aAST method def to check
 * @return true if this is a readObject() definition
 */
private boolean isReadObject(DetailAST aAST)
{
    // name is readObject...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"readObject".equals(ident.getText())) {
        return false;
    }

    // returns void...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.LITERAL_VOID) {
        return false;
    }

    // should have one parameter...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params == null || params.getChildCount() != 1) {
        return false;
    }
    // and paramter's type should be java.io.ObjectInputStream
    final DetailAST type =
        (DetailAST) ((DetailAST) params.getFirstChild())
            .findFirstToken(TokenTypes.TYPE).getFirstChild();
    final String typeName = FullIdent.createFullIdent(type).getText();
    if (!"java.io.ObjectInputStream".equals(typeName)
        && !"ObjectInputStream".equals(typeName))
    {
        return false;
    }

    // and, finally, it should throws java.io.IOException
    // and java.lang.ClassNotFoundException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 3) {
        return false;
    }
    final DetailAST excpt1 = (DetailAST) throwsAST.getFirstChild();
    final String exception1 = FullIdent.createFullIdent(excpt1).getText();
    final String exception2 =
        FullIdent.createFullIdent(throwsAST.getLastChild()).getText();
    if (!"java.io.IOException".equals(exception1)
        && !"IOException".equals(exception1)
        && !"java.io.IOException".equals(exception2)
        && !"IOException".equals(exception2)
        || !"java.lang.ClassNotFoundException".equals(exception1)
        && !"ClassNotFoundException".equals(exception1)
        && !"java.lang.ClassNotFoundException".equals(exception2)
        && !"ClassNotFoundException".equals(exception2))
    {
        return false;
    }

    return true;
}
 

/**
 * Checks if a given method is writeReplace() or readResolve().
 * @param aAST method def to check
 * @return true if this is a writeReplace() definition
 */
private boolean isWriteReplaceOrReadResolve(DetailAST aAST)
{
    // name is writeReplace or readResolve...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"writeReplace".equals(ident.getText())
        && !"readResolve".equals(ident.getText()))
    {
        return false;
    }

    // returns Object...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.DOT
        && typeAST.getType() != TokenTypes.IDENT)
    {
        return false;
    }

    // should have no parameters...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params != null && params.getChildCount() != 0) {
        return false;
    }

    // and, finally, it should throws java.io.ObjectStreamException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 1) {
        return false;
    }
    final DetailAST excpt = (DetailAST) throwsAST.getFirstChild();
    final String exception = FullIdent.createFullIdent(excpt).getText();
    if (!"java.io.ObjectStreamException".equals(exception)
        && !"ObjectStreamException".equals(exception))
    {
        return false;
    }

    return true;
}
 

/**
 * Checks if a given method is writeObject().
 * @param aAST method def to check
 * @return true if this is a writeObject() definition
 */
private boolean isWriteObject(DetailAST aAST)
{
    // name is writeObject...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"writeObject".equals(ident.getText())) {
        return false;
    }

    // returns void...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.LITERAL_VOID) {
        return false;
    }

    // should have one parameter...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params == null || params.getChildCount() != 1) {
        return false;
    }
    // and paramter's type should be java.io.ObjectOutputStream
    final DetailAST type =
        (DetailAST) ((DetailAST) params.getFirstChild())
            .findFirstToken(TokenTypes.TYPE).getFirstChild();
    final String typeName = FullIdent.createFullIdent(type).getText();
    if (!"java.io.ObjectOutputStream".equals(typeName)
        && !"ObjectOutputStream".equals(typeName))
    {
        return false;
    }

    // and, finally, it should throws java.io.IOException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 1) {
        return false;
    }
    final DetailAST expt = (DetailAST) throwsAST.getFirstChild();
    final String exceptionName = FullIdent.createFullIdent(expt).getText();
    if (!"java.io.IOException".equals(exceptionName)
        && !"IOException".equals(exceptionName))
    {
        return false;
    }

    return true;
}
 

/**
 * Checks if a given method is readObject().
 * @param aAST method def to check
 * @return true if this is a readObject() definition
 */
private boolean isReadObject(DetailAST aAST)
{
    // name is readObject...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"readObject".equals(ident.getText())) {
        return false;
    }

    // returns void...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.LITERAL_VOID) {
        return false;
    }

    // should have one parameter...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params == null || params.getChildCount() != 1) {
        return false;
    }
    // and paramter's type should be java.io.ObjectInputStream
    final DetailAST type =
        (DetailAST) ((DetailAST) params.getFirstChild())
            .findFirstToken(TokenTypes.TYPE).getFirstChild();
    final String typeName = FullIdent.createFullIdent(type).getText();
    if (!"java.io.ObjectInputStream".equals(typeName)
        && !"ObjectInputStream".equals(typeName))
    {
        return false;
    }

    // and, finally, it should throws java.io.IOException
    // and java.lang.ClassNotFoundException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 3) {
        return false;
    }
    final DetailAST excpt1 = (DetailAST) throwsAST.getFirstChild();
    final String exception1 = FullIdent.createFullIdent(excpt1).getText();
    final String exception2 =
        FullIdent.createFullIdent(throwsAST.getLastChild()).getText();
    if (!"java.io.IOException".equals(exception1)
        && !"IOException".equals(exception1)
        && !"java.io.IOException".equals(exception2)
        && !"IOException".equals(exception2)
        || !"java.lang.ClassNotFoundException".equals(exception1)
        && !"ClassNotFoundException".equals(exception1)
        && !"java.lang.ClassNotFoundException".equals(exception2)
        && !"ClassNotFoundException".equals(exception2))
    {
        return false;
    }

    return true;
}
 

/**
 * Checks if a given method is writeReplace() or readResolve().
 * @param aAST method def to check
 * @return true if this is a writeReplace() definition
 */
private boolean isWriteReplaceOrReadResolve(DetailAST aAST)
{
    // name is writeReplace or readResolve...
    final DetailAST ident = aAST.findFirstToken(TokenTypes.IDENT);
    if (!"writeReplace".equals(ident.getText())
        && !"readResolve".equals(ident.getText()))
    {
        return false;
    }

    // returns Object...
    final DetailAST typeAST =
        (DetailAST) aAST.findFirstToken(TokenTypes.TYPE).getFirstChild();
    if (typeAST.getType() != TokenTypes.DOT
        && typeAST.getType() != TokenTypes.IDENT)
    {
        return false;
    }

    // should have no parameters...
    final DetailAST params = aAST.findFirstToken(TokenTypes.PARAMETERS);
    if (params != null && params.getChildCount() != 0) {
        return false;
    }

    // and, finally, it should throws java.io.ObjectStreamException
    final DetailAST throwsAST =
        aAST.findFirstToken(TokenTypes.LITERAL_THROWS);
    if (throwsAST == null || throwsAST.getChildCount() != 1) {
        return false;
    }
    final DetailAST excpt = (DetailAST) throwsAST.getFirstChild();
    final String exception = FullIdent.createFullIdent(excpt).getText();
    if (!"java.io.ObjectStreamException".equals(exception)
        && !"ObjectStreamException".equals(exception))
    {
        return false;
    }

    return true;
}