public BooleanExpression contains(Expression<String> str) {
        return Expressions.booleanOperation(Ops.STRING_CONTAINS, mixin, str);
    }
Create a {@code this.contains(str)} expression

<p>Returns true if the given String is contained</p>

@param str string
@return this.contains(str)
@see java.lang.String#contains(CharSequence)
querydsl-core/src/main/java/com/querydsl/core/types/dsl/StringExpression.java