javax.servlet.jsp.jstl.core.LoopTagStatus Maven / Gradle / Ivy
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* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
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*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
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* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
*
* Portions Copyright Apache Software Foundation.
*/
package javax.servlet.jsp.jstl.core;
/**
* Exposes the current status of
* an iteration. JSTL provides a mechanism for LoopTags to
* return information about the current index of the iteration and
* convenience methods to determine whether or not the current round is
* either the first or last in the iteration. It also lets authors
* use the status object to obtain information about the iteration range,
* step, and current object.
*
* Environments that require more status can extend this interface.
*
* @author Shawn Bayern
*/
public interface LoopTagStatus {
/**
* Retrieves the current item in the iteration. Behaves
* idempotently; calling getCurrent() repeatedly should return the same
* Object until the iteration is advanced. (Specifically, calling
* getCurrent() does not advance the iteration.)
*
* @return the current item as an object
*/
public Object getCurrent();
/**
* Retrieves the index of the current round of the iteration. If
* iteration is being performed over a subset of an underlying
* array, java.lang.Collection, or other type, the index returned
* is absolute with respect to the underlying collection. Indices
* are 0-based.
*
* @return the 0-based index of the current round of the iteration
*/
public int getIndex();
/**
* Retrieves the "count" of the current round of the iteration. The
* count is a relative, 1-based sequence number identifying the
* current "round" of iteration (in context with all rounds the
* current iteration will perform).
*
* As an example, an iteration with begin = 5, end = 15, and step =
* 5 produces the counts 1, 2, and 3 in that order.
*
* @return the 1-based count of the current round of the iteration
*/
public int getCount();
/**
* Returns information about whether the current round of the
* iteration is the first one. This current round may be the 'first'
* even when getIndex() != 0, for 'index' refers to the absolute
* index of the current 'item' in the context of its underlying
* collection. It is always that case that a true result from
* isFirst() implies getCount() == 1.
*
* @return true if the current round is the first in the
* iteration, false otherwise.
*/
public boolean isFirst();
/**
* Returns information about whether the current round of the
* iteration is the last one. As with isFirst(), subsetting is
* taken into account. isLast() doesn't necessarily refer to the
* status of the underlying Iterator; it refers to whether or not
* the current round will be the final round of iteration for the
* tag associated with this LoopTagStatus.
*
* @return true if the current round is the last in the
* iteration, false otherwise.
*/
public boolean isLast();
/**
* Returns the value of the 'begin' attribute for the associated tag,
* or null if no 'begin' attribute was specified.
*
* @return the 'begin' value for the associated tag, or null
* if no 'begin' attribute was specified
*/
public Integer getBegin();
/**
* Returns the value of the 'end' attribute for the associated tag,
* or null if no 'end' attribute was specified.
*
* @return the 'end' value for the associated tag, or null
* if no 'end' attribute was specified
*/
public Integer getEnd();
/**
* Returns the value of the 'step' attribute for the associated tag,
* or null if no 'step' attribute was specified.
*
* @return the 'step' value for the associated tag, or null
* if no 'step' attribute was specified
*/
public Integer getStep();
}