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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 be published to the event hub.
 * The parameter type should be OutputBinding<T>, where T could be one of:
 *
 * 
 *     Any native Java types such as int, String, byte[]
 *     Any POJO type
 * 
 *
 * The following example shows a Java function that writes a message to an event hub:
 * 
 * {@literal @}FunctionName("sendTime")
 *{@literal @}EventHubOutput(name = "event", eventHubName = "samples-workitems", connection = "AzureEventHubConnection")
 * public String sendTime(
 *    {@literal @}TimerTrigger(name = "sendTimeTrigger", schedule = "0 */5 * * * *") String timerInfo
 * ) {
 *     return LocalDateTime.now().toString();
 * }
 *
 * @since 1.0.0
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.PARAMETER, ElementType.METHOD})
public @interface EventHubOutput {
    /**
     * 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:
     * 
     *     "" or string: treat it as a string whose value is serialized from the parameter
     *     binary: treat it as a binary data whose value comes from for example OutputBinding<byte[]>
     * 
     * @return The dataType which will be used by the Functions runtime.
     */
    String dataType() default "";

    /**
     * Defines the name of the event hub to which to publish.
     * @return The event hub name string.
     */
    String eventHubName();

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