NoClassDefFoundError when trying to run DaoGenerator for GreenDAO

Question

I have an Android Project, using Android Studio 2.3, which uses GreenDAO to generate the classes to interact with the SQLite database. The DaoGenerator project always worked before... but today I just needed to add 2 columns/properties to an Entity and whenever I try to run the generator project, I get the following error:

Exception in thread "main" java.lang.NoClassDefFoundError: org/greenrobot/greendao/generator/Schema
    at com.company.daogenerator.ProjectDaoGenerator.main(ProjectDaoGenerator.java:20)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.ClassNotFoundException: org.greenrobot.greendao.generator.Schema
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

I'm using GreenDAO 3.2.0 in my application's Gradle file:

compile 'org.greenrobot:greendao:3.2.0'

Also, in DaoGenerator's Gradle file:

apply plugin: 'java'

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'org.greenrobot:greendao-generator:3.2.0'
}

My ProjectDaoGenerator.java file:

package com.company.daogenerator;

import org.greenrobot.greendao.generator.DaoGenerator;
import org.greenrobot.greendao.generator.Entity;
import org.greenrobot.greendao.generator.Property;
import org.greenrobot.greendao.generator.Schema;

public class ProjectDaoGenerator {
    private static Entity primaryKeyEntity;
    private static Entity itemTypeEntity;

    public static void main(String args[]) throws Exception {
        Schema schema = new Schema(1, "com.company.project.datamodel");
        schema.enableKeepSectionsByDefault();

        // Define entities
        Entity primaryKey = schema.addEntity("CDPrimaryKey");
        Entity installation = schema.addEntity("CDInstallation");

        // Z_PRIMARYKEY
        primaryKeyEntity = primaryKey;
        primaryKey.setTableName("Z_PRIMARYKEY");
        primaryKey.addLongProperty("ENT").columnName("Z_ENT").primaryKey();
        primaryKey.addIntProperty("MAX").columnName("Z_MAX");
        primaryKey.addStringProperty("NAME").columnName("Z_NAME");
        primaryKey.addIntProperty("SUPER").columnName("Z_INT");

        // CDInstallation
        installation.setTableName("ZCDINSTALLATION");
        installation.addLongProperty("packageDate").columnName("ZPACKAGEDATE");

        (...) // Other Properties

        // **** Generate Schema ****
        new DaoGenerator().generateAll(schema, "app/src/main/java");
    }
}

It's as if it couldn't find org.greenrobot.greendao.generator.Schema.

score 14 · Accepted Answer · edited Feb 23 '18 at 09:27

14

Set the build.gradle file for your generator like this (especially note the mainClassName):

Then click the "Gradle" tab in the right sidebar of Android Studio and select the "run" task of your daogenerator like this:

It's worked for me , more details check link : https://github.com/greenrobot/greenDAO/issues/619 http://greenrobot.org/greendao/documentation/generator/#Triggering_generation

edited Feb 23 '18 at 09:27

andygeers

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answered Nov 09 '17 at 11:04

jesto paul

438
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I can't work out where this second screenshot has come from - how do you get to this "Gradle" view? – andygeers Feb 22 '18 at 15:54
are you coding in Android Studio then you can easily see Gradle in right sidebar.If there is you can't see, then double click on shift button -> search box come - > just type "Gradle" -> then you can see gradle (first in list). – jesto paul Feb 23 '18 at 04:26
After doing this for me its causing duplicate member variables – Aniruddha K.M Mar 01 '18 at 14:15
@war_Hero Make sure you do not include your same objects variable twice in your daoGenerator. – jesto paul Mar 02 '18 at 04:40
Yup, checked it instead of replacing the old member variables the new ones are getting added again – Aniruddha K.M Mar 02 '18 at 04:42
@jestopaul it was mismatch in configuration, it was my issue thanks for your help. – Aniruddha K.M Mar 02 '18 at 08:34

score 2 · Answer 2 · answered Jan 11 '18 at 09:43

2

Apart from what @Jesto Paul mentioned, I changed the following in the Generator class

new DaoGenerator().generateAll(schema, "./app/src/main/java"); - shows Path not exist.

to

new DaoGenerator().generateAll(schema, "../app/src/main/java");

(added double dot for the path). After doing this the generator create the tables to the folder.

answered Jan 11 '18 at 09:43

droid kid

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Thank you. Adding ../ helped me. – Nagesh Jatagond May 08 '18 at 05:55

BenRoob · Answer 3 · 2017-06-02T08:56:11.657

1

For some reason, I ran into the same problem after updating android buildToolsVersion.

After some time of searching, i've accidentally checked "Run > Edit Configurations..." for the DaoGenerator-Application.

In the list of JRE "Android API 25 Platform" was selected. So I changed it back to the external Java running on my computer (e.g. "1.8", did it before some days ago). That solved it for me.

Edit: in this project I use GreenDAO 2.1.0

Edit 2:

https://github.com/greenrobot/greenDAO/issues/619 - http://greenrobot.org/greendao/documentation/generator/#Triggering_generation

edited Jun 02 '17 at 08:56

answered Apr 13 '17 at 12:34

BenRoob

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Have you tried a clean, rebuild (make module) etc? I had an extra generator module, moved that code to our app module. Sorry, don't remember if I have changed the JRE before or after that. Please have a look at this issue and team's advise: https://github.com/greenrobot/greenDAO/issues/619 – BenRoob Jun 02 '17 at 08:47

NoClassDefFoundError when trying to run DaoGenerator for GreenDAO

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