private void generatePrepareRequest()

in mapper-processor/src/main/java/com/datastax/oss/driver/internal/mapper/processor/dao/DaoIncrementMethodGenerator.java [228:315]
69 lines of code
8 McCabe index (conditional complexity)

  private void generatePrepareRequest(
      MethodSpec.Builder methodBuilder,
      String requestName,
      EntityDefinition entityDefinition,
      String helperFieldName,
      List<? extends VariableElement> incrementParameters) {

    if (incrementParameters.isEmpty()) {
      context
          .getMessager()
          .error(
              methodElement,
              "%s method must take at least one parameter representing an increment to a "
                  + "counter column",
              Increment.class.getSimpleName());
      return;
    }

    methodBuilder
        .addStatement("$L.throwIfKeyspaceMissing()", helperFieldName)
        .addCode(
            "$[$1T $2L = (($3L.getKeyspaceId() == null)\n"
                + "? $4T.update($3L.getTableId())\n"
                + ": $4T.update($3L.getKeyspaceId(), $3L.getTableId()))",
            SimpleStatement.class,
            requestName,
            helperFieldName,
            QueryBuilder.class);

    // Add an increment clause for every non-PK parameter. Example: for a parameter `long oneStar`
    // =>  `.append("one_star", QueryBuilder.bindMarker("oneStar"))`
    for (VariableElement parameter : incrementParameters) {
      CodeBlock cqlName = null;
      CqlName annotation = parameter.getAnnotation(CqlName.class);
      if (annotation != null) {
        // If a CQL name is provided, use that
        cqlName = CodeBlock.of("$S", annotation.value());
      } else {
        // Otherwise, try to match the parameter to an entity property based on the names, for
        // example parameter `oneStar` matches `ProductRating.getOneStar()`.
        for (PropertyDefinition property : entityDefinition.getRegularColumns()) {
          if (property.getJavaName().equals(parameter.getSimpleName().toString())) {
            cqlName = property.getCqlName();
            break;
          }
        }
        if (cqlName == null) {
          List<String> javaNames =
              StreamSupport.stream(entityDefinition.getRegularColumns().spliterator(), false)
                  .map(PropertyDefinition::getJavaName)
                  .collect(Collectors.toList());
          context
              .getMessager()
              .error(
                  parameter,
                  "Could not match '%s' with any counter column in %s (expected one of: %s). "
                      + "You can also specify a CQL name directly with @%s.",
                  parameter.getSimpleName(),
                  entityDefinition.getClassName().simpleName(),
                  javaNames,
                  CqlName.class.getSimpleName());
          // Don't return abruptly, execute the rest of the method to finish the Java statement
          // cleanly (otherwise JavaPoet throws an error). The generated statement will be
          // incorrect, but that doesn't matter since we've already thrown a compile error.
          break;
        }
      }

      // Always use the parameter name. This is what the binding code will expect (see
      // GeneratedCodePatterns.bindParameters call in generate())
      String bindMarkerName = parameter.getSimpleName().toString();

      // We use `append` to generate "c=c+?". QueryBuilder also has `increment` that produces
      // "c+=?", but that doesn't work with Cassandra 2.1.
      methodBuilder.addCode(
          "\n.append($1L, $2T.bindMarker($3S))", cqlName, QueryBuilder.class, bindMarkerName);
    }

    for (PropertyDefinition property : entityDefinition.getPrimaryKey()) {
      methodBuilder.addCode(
          "\n.where($1T.column($2L).isEqualTo($3T.bindMarker($2L)))",
          Relation.class,
          property.getCqlName(),
          QueryBuilder.class);
    }

    methodBuilder.addCode("\n.build()$];\n");
  }