Performance : Parameterized Constructor in Grails for Domain Objects

Don't use parametereized constructor in Grails for domain objects. This is slower than empty constructor.

This performance issue become significant when creating large number of domain objects in loop.

Overriding equals in Groovy

I was overriding equals method in for a Groovy class and got into StackOverflow error.

class ObjKey {
    long id
    String value

    public boolean equals(Object obj) {
        if (!(obj instanceof ObjKey)) {
            return false;
        }
        if (this == obj) {
            return true;
        }
        ObjKey rhs = (ObjKey) obj;
        return new EqualsBuilder()
            .append(id, rhs?.id)
            .append(value, rhs?.value)
            .isEquals();
    }

    public int hashCode() {
        return new HashCodeBuilder()
        .append(id)
        .append(value)
        .toHashCode();
    }
}

I was getting stackoverflow at line: if (this == obj). Groovy's equals calls the equals method instead of comparing the reference.

I fixed it using bellow syntax: if (this.is(obj)). The corrected code looks like:

class ObjKey {
    long id
    String value

    public boolean equals(Object obj) {
        if (!(obj instanceof ObjKey)) {
            return false;
        }
        if (this.is(obj)) {
            return true;
        }
        ObjKey rhs = (ObjKey) obj;
        return new EqualsBuilder()
            .append(id, rhs?.id)
            .append(value, rhs?.value)
            .isEquals();
    }

    public int hashCode() {
        return new HashCodeBuilder()
        .append(id)
        .append(value)
        .toHashCode();
    }
}

Improving Grails Batch Processing

Batch Import Performance with Grails and MySQL

log.debug not working in grails unit test

Use the following method call to enable debug level messages to be printed.

mockLogging(grails_artifact_class, true)

where, grails_artifact_class is domain/controller/service class.

Exception while starting grails from STS

Problem: Getting java.lang.ClassNotFoundException: sun.tools.native2ascii.Main while starting grails application from STS.

Solution: Go to build path. Change your default system JRE to JDK. You are good!