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I was not able to create hello world smart contract with neo-devpack-java.

1. maybe documentation is old
2. or in neo-devpack-java are some java files missing

Documentation tells us to extends our smart contracts with FunctionCode or VerificationCode.

Example from doc

import AntShares.SmartContract.Framework.FunctionCode;
import AntShares.SmartContract.Framework.Services.AntShares.Storage;

public class HelloWorld extends FunctionCode{
    public static byte[] Main(String[] args){
        Storage.Put(Storage.getCurrentContext(), "Greeting to the World", "Hello World!");
        return Storage.Get(Storage.getCurrentContext(),"Greeting to the World");
    }
}

Neo-devpack-java doesnt contain this files.

Link to Antshares.SmartContract.Framework JAR by documentation is broken.

I found one issue telling that Antshares.SmartContract.Framework JAR is compiled from neo-devpack-java.

If so than above mentioned documentation is old or neo-devpack-java is missing java files.

Dear devs,

When calling ExecutionEngine.callingScriptHash() from org.neo.smartcontract.framework.services.system we are experiencing a problem when verifying another smart contract.

When the function is called in Main(), it gives the correct smart contract caller hash. Like so:

public class Token extends SmartContract{

    // main
    public static Object Main(String operation, Object[] args) {

        // correct hash 
        byte[] caller = (byte[]) ExecutionEngine.callingScriptHash();

    }

}

However, when calling the script from a nested function in Main(), for example someFunction() that returns a boolean is gives a different and incorrect hash when the script is called. Like so:

public class Token extends SmartContract{

    // some function
    public static boolean someFuntion() {

        // wrong and different hash!
        byte[] caller = (byte[]) ExecutionEngine.callingScriptHash(); //  < ----

        return true;
    }

    // main
    public static Object Main(String operation, Object[] args) {

        // function call
        someFuntion();

    }

}

Could you help me? How can we avoid this situation? I can provide more info. We can not verify a script now. Are we doing something wrong maybe?

Travis CI can be used for open source projects to have continuous builds and nice mark telling if project can be build or not.

Hello,

We need upload neo-devpack-java jar artifact to maven central repository. Tutorial page how to achieve it is here.

After that we can write smart contracts with just maven pom dependency and not add it manualy to classpath like we do right now. It is easier and standard way for Java developers.

Example of one smart contract pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>org.learning.neo</groupId>
    <artifactId>hello-world-smart-contract</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>My first smart contract</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
        <maven.compiler.plugin.version>3.6.1</maven.compiler.plugin.version>
    </properties>

    <build>
        <sourceDirectory>src</sourceDirectory>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>${maven.compiler.plugin.version}</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                    <encoding>${project.build.sourceEncoding}</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

  <dependencies>
        <dependency>
            <groupId>org.neo.smartcontract.framework</groupId>
            <artifactId>neo-devpack-java</artifactId>
            <version>2.3.0</version>
        </dependency>
    </dependencies>
</project>

I can do it if you agree with it. And after that i will start contribute examples to neo-project/examples-java project.

After maven clean package the build ends up with

illegal character: '\ufeff'

and

unmappable character for encoding UTF8

Deleting the BOM '\ufeff' is needed from Java source code.

Maven's version of framework is nopt up to date, there is not Runtime.time().