MetricStorageRegistry

java.lang.Object
- io.opentelemetry.sdk.metrics.internal.state.MetricStorageRegistry

```
public class MetricStorageRegistry
extends java.lang.Object
```
Responsible for storing metrics by MetricDescriptor and returning access to input pipeline for instrument measurements.
Each descriptor in the registry results in an exported metric stream. Under normal circumstances each descriptor shares a unique MetricDescriptor.getName(). When multiple descriptors share the same name, but have some difference in identifying fields, an identity conflict has occurred. The registry detects identity conflicts on register(MetricStorage) and logs diagnostic information when they occur. See MetricDescriptor.equals(Object) for definition of identity equality.
This class is internal and is hence not for public use. Its APIs are unstable and can change at any time.

Field Summary

Fields
Modifier and Type	Field	Description
`private java.lang.Object`	`lock`
`private static java.util.logging.Logger`	`logger`
`private java.util.Map<MetricDescriptor,MetricStorage>`	`registry`

Constructor Summary

Constructors
Constructor Description

MetricStorageRegistry()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`java.util.Collection<MetricStorage>`	`getStorages()`	Returns a `Collection` of the registered `MetricStorage`.
`<I extends MetricStorage> I`	`register(I newStorage)`	Registers the metric `newStorage` to this registry.
`void`	`resetForTest()`	Reset the storage registry, clearing all storages.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - logger
```
private static final java.util.logging.Logger logger
```
  - lock
```
private final java.lang.Object lock
```
  - registry
```
private final java.util.Map<MetricDescriptor,MetricStorage> registry
```
- Constructor Detail
  - MetricStorageRegistry
```
public MetricStorageRegistry()
```
- Method Detail
  - getStorages
```
public java.util.Collection<MetricStorage> getStorages()
```
    Returns a Collection of the registered MetricStorage.
  - register
```
public <I extends MetricStorage> I register(I newStorage)
```
    Registers the metric newStorage to this registry. If a metric with compatible identity was previously registered, returns the previously registered storage. If a metric with the same name (case-insensitive) but incompatible MetricDescriptor was previously registered, logs a diagnostic warning and returns the newStorage.
    
    Parameters:
    
    newStorage - the metric storage to use or discard.
    
    Returns:
    
    the newStorage if no compatible metric is already registered, otherwise the previously registered storage.
  - resetForTest
```
public void resetForTest()
```
    Reset the storage registry, clearing all storages.