public BooleanExpression eq(T right) {
        if (right == null) {
            throw new IllegalArgumentException("eq(null) is not allowed. Use isNull() instead");
        } else {
            return eq(ConstantImpl.create(right));
        }
    }
Create a {@code this == right} expression

<p>Use expr.isNull() instead of expr.eq(null)</p>

@param right rhs of the comparison
@return this == right
querydsl-core/src/main/java/com/querydsl/core/types/dsl/SimpleExpression.java