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无法使用java eclipse通过lambda函数将项插入dynamodb

我试图通过lambda函数将项目插入dynamodb。 我已经提供了创建iam角色和lambda函数所需的所有凭据。 但我的程序抛出以下异常

{
  "errorMessage": "com/amazonaws/client/builder/AwsSyncClientBuilder",
  "errorType": "java.lang.NoClassDefFoundError",
  "stackTrace": [
    "java.lang.ClassLoader.defineClass1(Native Method)",
    "java.lang.ClassLoader.defineClass(ClassLoader.java:763)",
    "java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)",
    "java.net.URLClassLoader.defineClass(URLClassLoader.java:467)",
    "java.net.URLClassLoader.access$100(URLClassLoader.java:73)",
    "java.net.URLClassLoader$1.run(URLClassLoader.java:368)",
    "java.net.URLClassLoader$1.run(URLClassLoader.java:362)",
    "java.security.AccessController.doPrivileged(Native Method)",
    "java.net.URLClassLoader.findClass(URLClassLoader.java:361)",
    "java.lang.ClassLoader.loadClass(ClassLoader.java:424)",
    "java.lang.ClassLoader.loadClass(ClassLoader.java:357)",
    "com.bridgelabz.LambdaFunctionHandler.handleRequest(LambdaFunctionHandler.java:20)",
    "com.bridgelabz.LambdaFunctionHandler.handleRequest(LambdaFunctionHandler.java:1)"
  ],
  "cause": {
    "errorMessage": "com.amazonaws.client.builder.AwsSyncClientBuilder",
    "errorType": "java.lang.ClassNotFoundException",
    "stackTrace": [
      "java.net.URLClassLoader.findClass(URLClassLoader.java:381)",
      "java.lang.ClassLoader.loadClass(ClassLoader.java:424)",
      "java.lang.ClassLoader.loadClass(ClassLoader.java:357)",
      "java.lang.ClassLoader.defineClass1(Native Method)",
      "java.lang.ClassLoader.defineClass(ClassLoader.java:763)",
      "java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)",
      "java.net.URLClassLoader.defineClass(URLClassLoader.java:467)",
      "java.net.URLClassLoader.access$100(URLClassLoader.java:73)",
      "java.net.URLClassLoader$1.run(URLClassLoader.java:368)",
      "java.net.URLClassLoader$1.run(URLClassLoader.java:362)",
      "java.security.AccessController.doPrivileged(Native Method)",
      "java.net.URLClassLoader.findClass(URLClassLoader.java:361)",
      "java.lang.ClassLoader.loadClass(ClassLoader.java:424)",
      "java.lang.ClassLoader.loadClass(ClassLoader.java:357)",
      "com.bridgelabz.LambdaFunctionHandler.handleRequest(LambdaFunctionHandler.java:20)",
      "com.bridgelabz.LambdaFunctionHandler.handleRequest(LambdaFunctionHandler.java:1)"
    ]
  }
}

这是我的密码

package com.bridgelabz;

import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import com.amazonaws.services.dynamodbv2.document.DynamoDB;
import com.amazonaws.services.dynamodbv2.document.Item;
import com.amazonaws.services.dynamodbv2.document.Table;
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;

import com.amazonaws.services.lambda.runtime.events.DynamodbEvent;

public class LambdaFunctionHandler implements RequestHandler<DynamodbEvent, Object> {

    @Override
    public Object handleRequest(DynamodbEvent input, Context context) {
        context.getLogger().log("Input: " + input);

        AmazonDynamoDB client = AmazonDynamoDBClientBuilder.standard().withRegion(Regions.US_WEST_2).build();
        DynamoDB dynamoDB = new DynamoDB(client);
        String tableName = "AddNumbers";

        Table table = dynamoDB.getTable(tableName);
        Model model = new Model();

        int uniqueId = model.getUniqueId();
        int number1 = model.getNumber1();
        int number2 = model.getNumber2();
        int result = number1 + number2;

        Item item = new Item().withPrimaryKey("uniqueId", uniqueId).withNumber("number1", number1)
                .withNumber("number2", number2).withNumber("result1", result);

        table.putItem(item);

        return true;
    }

}

还有我的模范班

package com.bridgelabz;

public class Model {

    int uniqueId;
    int number1;
    int number2;

    public int getUniqueId() {
        return uniqueId;
    }

    public void setUniqueId(int uniqueId) {
        this.uniqueId = uniqueId;
    }

    public int getNumber1() {
        return number1;
    }

    public void setNumber1(int number1) {
        this.number1 = number1;
    }

    public int getNumber2() {
        return number2;
    }

    public void setNumber2(int number2) {
        this.number2 = number2;
    }

}

表格是在dynamodb中预先创建的。我似乎无法理解我做错了什么。请帮忙


共 (1) 个答案

  1. # 1 楼答案

    您是否使用AWS SDK Eclipse插件上传代码?还是你自己?(使用aws cli导出JAR和上载)

    我编写了一个Java Lambda函数来接受一行,并将其输入DynamoDB;使用Eclipse导出将代码导出到JAR,并使用AWS cli将其上载到AWS,并获得NoClassDefError

    Error loading class <xyz>.MFZLambdaStoreEvents: com/amazonaws/AmazonServiceException: class java.lang.NoClassDefFoundError
    java.lang.NoClassDefFoundError: com/amazonaws/AmazonServiceException
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:348)
    

    如果我只有一个没有AWS SDK依赖项的简单函数,我就不会出现上述错误

    然后我遇到了http://docs.aws.amazon.com/toolkit-for-eclipse/v1/user-guide//lambda-tutorial.html 并且了解到我可以使用Eclipse-AWSSDK插件直接上传代码

    我尝试过这样做,现在我的函数成功运行了

    我的试用代码中的一些代码片段

    import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
    import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
    import com.amazonaws.services.dynamodbv2.model.AttributeValue;
    import com.amazonaws.services.dynamodbv2.model.PutItemRequest;
    import com.amazonaws.services.dynamodbv2.model.PutItemResult;
    import com.amazonaws.services.lambda.runtime.Context;
    import com.amazonaws.services.lambda.runtime.RequestHandler;
    
    public class LambdaStoreEvents implements RequestHandler<StepsEvent, Response> {
    
        static AmazonDynamoDB dynamoDB;
    
        @Override
        public Response handleRequest(StepsEvent event, Context context) {    
    
        String tableName = "<tablename>";
        Map<String, AttributeValue> item = newItem(event);
        PutItemRequest putItemRequest = new PutItemRequest(tableName, item);
    
        dynamoDB = AmazonDynamoDBClient.builder().build();
        PutItemResult putItemResult = dynamoDB.putItem(putItemRequest);
    
        Response response = new Response(putItemResult.toString());
    
        return response;
    
    }