class IsNullPredicate extends Expression {

    private final Expression value;

    public IsNullPredicate(Expression value) {
        this.value = requireNonNull(value, "value is null");
    }

    public Expression getValue() {
        return value;
    }

    @Override
    public <R, C> R accept(AstVisitor<R, C> visitor, C context) {
        return visitor.visitIsNullPredicate(this, context);
    }

    @Override
    public boolean equals(Object o) {<FILL_FUNCTION_BODY>}

    @Override
    public int hashCode() {
        return Objects.hash(value);
    }
}

        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        IsNullPredicate that = (IsNullPredicate) o;
        return Objects.equals(value, that.value);
    
<methods>public non-sealed void <init>() ,public R accept(AstVisitor<R,C>, C) ,public final java.lang.String toString() <variables>