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This package contains all Java interfaces and annotations to interact with Microsoft Azure functions runtime.

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/**
 * Copyright (c) Microsoft Corporation. All rights reserved.
 * Licensed under the MIT License. See License.txt in the project root for
 * license information.
 */

package com.microsoft.azure.functions.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Place this on a parameter whose value would come from a storage queue, and causing the method to run when a new
 * item is pushed. The parameter type can be one of the following:
 *
 * 
 *     Any native Java types such as int, String, byte[]
 *     Nullable values using Optional<T>
 *     Any POJO type
 * 
 *
 * The following example shows a Java function that polls the "myqueue-items" queue and writes a log each time a
 * queue item is processed.
 *
 * {@literal @}FunctionName("queueMonitor")
 * public void logQueueItem(
 *    {@literal @}QueueTrigger(name = "msg", queueName = "myqueue-items", connection = "AzureWebJobsStorage") 
 *     String message,
 *     final ExecutionContext context
 * ) {
 *     context.getLogger().info("Queue message processed: " + message);
 * }
 *
 * @since 1.0.0
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PARAMETER)
public @interface QueueTrigger {
    /**
     * The variable name used in function.json.
     * @return The variable name used in function.json.
     */
    String name();

    /**
     * Defines how Functions runtime should treat the parameter value. Possible values are:
     * 
     *     "": get the value as a string, and try to deserialize to actual parameter type like POJO
     *     string: always get the value as a string
     *     binary: get the value as a binary data, and try to deserialize to actual parameter type byte[]
     * 
     * @return The dataType which will be used by the Functions runtime.
     */
    String dataType() default "";

    /**
     * Defines the name of the storage queue to which to bind.
     * @return The storage queue name string.
     */
    String queueName();

    /**
     * Defines the app setting name that contains the Azure Storage connection string.
     * @return The app setting name of the connection string.
     */
    String connection() default "";
}