Stow

StringTemplate 4 Object Wrapper

StringTemplate is © Copyright StringTemplate / Terence Parr 2014

Stow is © Copyright Dave Parfitt 2014

What is it?

Stow generates Java wrapper classes for StringTemplate4 template groups. This allows you to easily access your templates by method instead of using String based keys, and will also catch certain template parameter problems at compile time:

• renamed parameters
• removed parameters
• changes in parameter case

Installing

<dependency>
  <groupId>com.github.metadave</groupId>
  <artifactId>Stow</artifactId>
  <version>0.1-SNAPSHOT</version>
</dependency>

Example

The following example takes a StringTemplate group file (Greeting.stg), and generates two classes: DemoGreeting and DemoFancyName. Finally, a demo program uses these classes to generate output.

Greeting.stg

Greeting(YourName, MyName) ::= <<
Hello <YourName>, my name is <MyName>!
>>

FancyName(Name) ::= <<
  ~~~<Name>~~~
>>

Run stow with the following parameters:

• -java_package com.foo.bar
• -class_prefix Demo
• -dest /path/to/some_directory
• -stg resources/Greeting.stg

which generates:

package com.foo.bar;
import org.stringtemplate.v4.ST;
import org.stringtemplate.v4.STGroup;
import com.metadave.stow.AbstractStow;

// generated by stow
// https://github.com/metadave/stow
public class DemoGreeting implements AbstractStow {
    ST st;
    public static final String templateName = "Greeting";

    public DemoGreeting(STGroup g) {
        st = g.getInstanceOf(templateName);
    }

    public ST getST() {
        return st;
    }

    public DemoGreeting addYourName(AbstractStow val) {
        st.add("YourName", val.getST());
        return this;
    }

    public DemoGreeting addYourName(Object val) {
        st.add("YourName", val);
        return this;
    }

    public DemoGreeting addMyName(AbstractStow val) {
        st.add("MyName", val.getST());
        return this;
    }

    public DemoGreeting addMyName(Object val) {
        st.add("MyName", val);
        return this;
    }
}

and

package com.foo.bar;
import org.stringtemplate.v4.ST;
import org.stringtemplate.v4.STGroup;
import com.metadave.stow.AbstractStow;

// generated by stow
// https://github.com/metadave/stow
public class DemoFancyName implements AbstractStow {
    ST st;
    public static final String templateName = "FancyName";

    public DemoFancyName(STGroup g) {
        st = g.getInstanceOf(templateName);
    }

    public ST getST() {
        return st;
    }

    public DemoFancyName addName(AbstractStow val) {
        st.add("Name", val.getST());
        return this;
    }

    public DemoFancyName addName(Object val) {
        st.add("Name", val);
        return this;
    }
}

The snippet of code below shows basic usage of the generated code:

STGroup stg = new STGroupFile("Greeting.stg");

DemoGreeting g = new DemoGreeting(stg);
g.addMyName("Dave");

DemoFancyName you = new DemoFancyName(stg);
you.addName("User");
// added as an ST object using the AbstractStow interface
g.addYourName(you);

System.out.println(g.getST().render());

When the code above is run, the following text is displayed in the console:

Hello ~~~User~~~, my name is Dave!

Integration with Maven

This needs some cleanup, it seems like my IDE picks up the generated classes but Maven doesn't.

Change the arguments -java_package, -class_prefix, -dest, and -stg in the monsterous snippet of XML below, and add to your pom.xml.

  <build>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.1.1</version>
                <executions>
                    <execution>
                        <id>RunStow</id>
                        <phase>compile</phase>
                        <goals>
                            <goal>exec</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <executable>java</executable>
                    <arguments>
                        <argument>-classpath</argument>
                        <classpath/>
                        <argument>com.metadave.stow.Stow</argument>

                        <argument>-java_package</argument>
                            <argument>com.foo.bar</argument>
                        <argument>-class_prefix</argument>
                            <argument>Demo</argument>
                        <argument>-dest</argument>
                            <argument>${project.build.sourceDirectory}/com/foo/bar</argument>
                        <argument>-stg</argument>
                            <argument>${project.build.sourceDirectory}/../resources/Demo.stg</argument>

                    </arguments>
                </configuration>
            </plugin>
        </plugins>
    </build>

Contributing

Fork this repo, create a branch with

git checkout -b your_branch_name

Submit a pull request when your code is ready for review.

License

http://www.apache.org/licenses/LICENSE-2.0.html

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© 2014 Dave Parfitt