Errors in Web3j-Generated Wrapper Classes: "Cannot find symbol: class LinkReference" and Incorrect Package Name

[abdul-mueed-shz]

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Title:
Errors in Web3j-Generated Wrapper Classes: "Cannot find symbol: class LinkReference" and Incorrect Package Name

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Body:

I'm working on a Spring Boot project that interacts with Ethereum smart contracts. I'm using Web3j to compile Solidity contracts and generate ABI, binary files, and Java wrapper classes. However, the generated wrapper classes contain the following issues:

1. Compilation Error:

   /home/abdulmueedshahbaz/springboot/eth/eth/src/main/java/generated/com/zuehlke/blockchain/model/HelloWorld.java:204:51
   java: cannot find symbol
     symbol:   class LinkReference
     location: class org.web3j.tx.Contract
   

   This error suggests that the class LinkReference is missing in the generated code.

Due to this issue, I'm unable to run my Spring Boot application.

My Setup:

Dependencies (Maven):

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>core</artifactId>
        <version>5.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>crypto</artifactId>
        <version>5.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>utils</artifactId>
        <version>5.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>abi</artifactId>
        <version>5.0.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.18.2</version>
    </dependency>
</dependencies>

Build Plugins (Maven):

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
        <plugin>
            <groupId>org.web3j</groupId>
            <artifactId>web3j-maven-plugin</artifactId>
            <version>4.12.3</version>
            <configuration>
                <packageName>com.zuehlke.blockchain.model</packageName>
                <sourceDestination>src/main/java/generated</sourceDestination>
                <nativeJavaType>true</nativeJavaType>
                <outputFormat>java,bin</outputFormat>
                <soliditySourceFiles>
                    <directory>src/main/resources/solidity/</directory>
                    <includes>
                        <include>**/*.sol</include>
                    </includes>
                </soliditySourceFiles>
                <outputDirectory>
                    <java>src/main/java/generated</java>
                    <bin>src/bin/generated</bin>
                    <abi>src/abi/generated</abi>
                </outputDirectory>
                <contract>
                    <includes>
                        <include>HelloWorld</include>
                    </includes>
                    <excludes>
                        <exclude>mortal</exclude>
                    </excludes>
                </contract>
                <pathPrefixes>
                    <pathPrefix>dep=../dependencies</pathPrefix>
                </pathPrefixes>
            </configuration>
        </plugin>
    </plugins>
</build>

Steps I Followed:

1. Added my Solidity files to src/main/resources/solidity/.
2. Ran mvn generate-sources to generate the ABI, binary, and wrapper classes.
3. Attempted to build and run the application.

Issues:

1. The HelloWorld.java wrapper class references a LinkReference class, which does not seem to exist in org.web3j.tx.Contract.

Question:

• How can I resolve the missing LinkReference error in the Web3j-generated wrapper classes
• Are there any known compatibility issues between Web3j (v5.0.0) and Solidity contracts?

Any guidance would be greatly appreciated!

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