http://www.jboss.org/undertow-parent/undertow-core: Undertow (JBoss by Red Hat) 
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 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
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 *  See the License for the specific language governing permissions and
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package io.undertow.attribute;

import io.undertow.server.HttpServerExchange;


Representation of a string attribute from a HTTP server exchange.

Author:Stuart Douglas
/**
 * Representation of a string attribute from a HTTP server exchange.
 *
 *
 * @author Stuart Douglas
 */
public interface ExchangeAttribute {

    
Resolve the attribute from the HTTP server exchange. This may return null if the attribute is not present.

Params:
  • exchange – The exchange
Returns:The attribute
/**
     * Resolve the attribute from the HTTP server exchange. This may return null if the attribute is not present.
     * @param exchange The exchange
     * @return The attribute
     */
    String readAttribute(final HttpServerExchange exchange);

    
Sets a new value for the attribute. Not all attributes are writable.

Params:
  • exchange – The exchange
  • newValue – The new value for the attribute
Throws:
/**
     * Sets a new value for the attribute. Not all attributes are writable.
     * @param exchange The exchange
     * @param newValue The new value for the attribute
     * @throws  ReadOnlyAttributeException when attribute cannot be written
     */
    void writeAttribute(final HttpServerExchange exchange, final String newValue) throws ReadOnlyAttributeException;
}