# Tutorial - User Guide { #tutorial-user-guide }

This tutorial shows you how to use **FastAPI** with most of its features, step by step.

Each section gradually builds on the previous ones, but it's structured to separate topics, so that you can go directly to any specific one to solve your specific API needs.

It is also built to work as a future reference so you can come back and see exactly what you need.

## Run the code { #run-the-code }

   *
   * @param key the key with which the specified value is to be associated
   * @param value the value to be associated with the specified key
   * @return the value that was previously associated with the key, or {@code null} if there was no
   *     previous entry. (If the bimap contains null values, then {@code forcePut}, like {@code
   *     put}, returns {@code null} both if the key is absent and if it is present with a null
   *     value.)

			atomic.StoreInt64(&dt.entries, 0)
			dt.mutex.Unlock()

			dt.adjust(logCopy)
			return
		}
		dt.mutex.Unlock()
	}
}

// adjust changes the value of the dynamic timeout based on the
// previous results
func (dt *dynamicTimeout) adjust(entries [dynamicTimeoutLogSize]time.Duration) {
	failures, maxDur := 0, time.Duration(0)
	for _, dur := range entries[:] {
		if dur == maxDuration {
			failures++

* Getting Logger Instance

 Starting with Maven 3.1.0, SLF4J Logger can be used directly. This technique can be used safely in Maven core
 components or in plugins/component not requiring compatibility with previous Maven versions.

+-----+
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MyClass
{
   final Logger logger = LoggerFactory.getLogger( MyClass.class );
}
+-----+

### Set metadata

In below example `minio-go` is used to set the storage class to `REDUCED_REDUNDANCY`. This means this object will be split across 6 data drives and 2 parity drives (as per the storage class set in previous step).

```go
s3Client, err := minio.New("localhost:9000", "YOUR-ACCESSKEYID", "YOUR-SECRETACCESSKEY", true)
if err != nil {
 log.Fatalln(err)
}

object, err := os.Open("my-testfile")
if err != nil {

### Testing an example with awscli tool

> Use the same username and password created in the previous steps.

```
[foobar]
region = us-east-1
aws_access_key_id = foobar
aws_secret_access_key = foo12345
```

/// info

The important point is that your app will be able to produce each line in turn, while the client consumes the previous lines.

///

/// note | Technical Details

        @Override
        public Integer next(Integer value) {
          return integers().next(value);
        }

        @Override
        public Integer previous(Integer value) {
          return integers().previous(value);
        }

        @Override
        public long distance(Integer start, Integer end) {
          return integers().distance(start, end);
        }
      };

...but continue reading below to see how to overcome that.

## Return Type and Data Filtering { #return-type-and-data-filtering }

Let's continue from the previous example. We wanted to **annotate the function with one type**, but we wanted to be able to return from the function something that actually includes **more data**.

    }

    @CanIgnoreReturnValue
    RoundToDoubleTester setExpectation(double expectedValue, RoundingMode... modes) {
      for (RoundingMode mode : modes) {
        Double previous = expectedValues.put(mode, expectedValue);
        if (previous != null) {
          throw new AssertionError();
        }
      }
      return this;
    }

    @CanIgnoreReturnValue