trunk/main/src/main/java/org/apache/jsieve/commands/AbstractPrologCommand.java

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package org.apache.jsieve.commands;

import org.apache.jsieve.SieveContext;
import org.apache.jsieve.exception.CommandException;

/**
 * <p>
 * Abstract class AbstractPrologCommand defines the common state validation
 * behavior for Prolog Commands. In RFC 3028 the only Prolog Command is
 * 'requires', however, the specification may evolve.
 * </p>
 */
public abstract class AbstractPrologCommand extends AbstractCommand {

    /**
     * Constructor for AbstractPrologCommand.
     */
    public AbstractPrologCommand() {
        super();
    }

    /**
     * <p>
     * Method validateState() ensures, via the CommandStateManager, that a
     * Prolog Command is permissible.
     * </p>
     * 
     * <p>
     * Also,
     * </p>
     * 
     * @see org.apache.jsieve.commands.AbstractCommand#validateState(SieveContext)
     */
    protected void validateState(SieveContext context) throws CommandException {
        super.validateState(context);

        if (!(context.getCommandStateManager().isInProlog()))
            throw context.getCoordinate().commandException(
                    "Invalid state for a prolog command.");
    }

}