# EventLog

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Summary:[Nested Classes](https://developer.android.com/reference/android/util/EventLog#nestedclasses)\|[Methods](https://developer.android.com/reference/android/util/EventLog#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/android/util/EventLog#inhmethods)  

# EventLog

*** ** * ** ***

[Kotlin](https://developer.android.com/reference/kotlin/android/util/EventLog "View this page in Kotlin")\|Java

`
public


class
EventLog
`  
`

extends `[Object](https://developer.android.com/reference/java/lang/Object)`


``


`

|---|-----------------------|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.util.EventLog |

<br />

*** ** * ** ***

Access to the system diagnostic event record. System diagnostic events are used to record certain system-level events (such as garbage collection, activity manager state, system watchdogs, and other low level activity), which may be automatically collected and analyzed during system development.

This is**not** the main "logcat" debugging log ([Log](https://developer.android.com/reference/android/util/Log))! These diagnostic events are for system integrators, not application authors.

Events use integer tag codes corresponding to /system/etc/event-log-tags. They carry a payload of one or more int, long, or String values. The event-log-tags file defines the payload contents for each type code.

## Summary

|                                                              ### Nested classes                                                               ||
|----------|-------------------------------------------------------------------------------------------------------------------------------------|
| ` class` | [EventLog.Event](https://developer.android.com/reference/android/util/EventLog.Event) A previously logged event read from the logs. |

|                                                                                                                                                                                                                              ### Public methods                                                                                                                                                                                                                              ||
|------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` static int`                                                                | ` `[getTagCode](https://developer.android.com/reference/android/util/EventLog#getTagCode(java.lang.String))`(`[String](https://developer.android.com/reference/java/lang/String)` name) ` Get the event type tag code associated with an event name.                                                                                                                                           |
| ` static `[String](https://developer.android.com/reference/java/lang/String) | ` `[getTagName](https://developer.android.com/reference/android/util/EventLog#getTagName(int))`(int tag) ` Get the name associated with an event type tag code.                                                                                                                                                                                                                                |
| ` static void`                                                               | ` `[readEvents](https://developer.android.com/reference/android/util/EventLog#readEvents(int[],%20java.util.Collection<android.util.EventLog.Event>))`(int[] tags, `[Collection](https://developer.android.com/reference/java/util/Collection)`<`[EventLog.Event](https://developer.android.com/reference/android/util/EventLog.Event)`> output) ` Read events from the log, filtered by type. |
| ` static int`                                                                | ` `[writeEvent](https://developer.android.com/reference/android/util/EventLog#writeEvent(int,%20java.lang.String))`(int tag, `[String](https://developer.android.com/reference/java/lang/String)` str) ` Record an event log message.                                                                                                                                                          |
| ` static int`                                                                | ` `[writeEvent](https://developer.android.com/reference/android/util/EventLog#writeEvent(int,%20int))`(int tag, int value) ` Record an event log message.                                                                                                                                                                                                                                      |
| ` static int`                                                                | ` `[writeEvent](https://developer.android.com/reference/android/util/EventLog#writeEvent(int,%20float))`(int tag, float value) ` Record an event log message.                                                                                                                                                                                                                                  |
| ` static int`                                                                | ` `[writeEvent](https://developer.android.com/reference/android/util/EventLog#writeEvent(int,%20java.lang.Object[]))`(int tag, `[Object...](https://developer.android.com/reference/java/lang/Object)` list) ` Record an event log message.                                                                                                                                                    |
| ` static int`                                                                | ` `[writeEvent](https://developer.android.com/reference/android/util/EventLog#writeEvent(int,%20long))`(int tag, long value) ` Record an event log message.                                                                                                                                                                                                                                    |

| ### Inherited methods |
|-----------------------|---|
| From class` `[java.lang.Object](https://developer.android.com/reference/java/lang/Object)` ` |--------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` `[Object](https://developer.android.com/reference/java/lang/Object)          | ` `[clone](https://developer.android.com/reference/java/lang/Object#clone())`() ` Creates and returns a copy of this object.                                                                                                                                                      | | ` boolean`                                                                     | ` `[equals](https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` obj) ` Indicates whether some other object is "equal to" this one.                                           | | ` void`                                                                        | ` `[finalize](https://developer.android.com/reference/java/lang/Object#finalize())`() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.                                                          | | ` final `[Class](https://developer.android.com/reference/java/lang/Class)`<?>` | ` `[getClass](https://developer.android.com/reference/java/lang/Object#getClass())`() ` Returns the runtime class of this`Object`.                                                                                                                                                | | ` int`                                                                         | ` `[hashCode](https://developer.android.com/reference/java/lang/Object#hashCode())`() ` Returns a hash code value for the object.                                                                                                                                                 | | ` final void`                                                                  | ` `[notify](https://developer.android.com/reference/java/lang/Object#notify())`() ` Wakes up a single thread that is waiting on this object's monitor.                                                                                                                            | | ` final void`                                                                  | ` `[notifyAll](https://developer.android.com/reference/java/lang/Object#notifyAll())`() ` Wakes up all threads that are waiting on this object's monitor.                                                                                                                         | | ` `[String](https://developer.android.com/reference/java/lang/String)          | ` `[toString](https://developer.android.com/reference/java/lang/Object#toString())`() ` Returns a string representation of the object.                                                                                                                                            | | ` final void`                                                                  | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long,%20int))`(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed. | | ` final void`                                                                  | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long))`(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed.                   | | ` final void`                                                                  | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait())`() ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*.                                                                                             | ||

## Public methods

### getTagCode

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int getTagCode (String name)
```

Get the event type tag code associated with an event name.

<br />

|                  Parameters                  ||
|--------|--------------------------------------|
| `name` | `String`: of event to look up <br /> |

|                          Returns                          ||
|-------|----------------------------------------------------|
| `int` | the tag code, or -1 if no tag has that name <br /> |

### getTagName

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static String getTagName (int tag)
```

Get the name associated with an event type tag code.

<br />

|              Parameters              ||
|-------|-------------------------------|
| `tag` | `int`: code to look up <br /> |

|                                                              Returns                                                              ||
|--------------------------------------------------------------------|---------------------------------------------------------------|
| [String](https://developer.android.com/reference/java/lang/String) | the name of the tag, or null if no tag has that number <br /> |

### readEvents

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static void readEvents (int[] tags, 
                Collection<EventLog.Event> output)
```

Read events from the log, filtered by type.

<br />

|                         Parameters                          ||
|----------|---------------------------------------------------|
| `tags`   | `int`: to search for <br />                       |
| `output` | `Collection`: container to add events into <br /> |

|                                                       Throws                                                       ||
|----------------------------------------------------------------------------|----------------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | if something goes wrong reading events |

### writeEvent

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int writeEvent (int tag, 
                String str)
```

Record an event log message.

<br />

|                  Parameters                  ||
|-------|---------------------------------------|
| `tag` | `int`: The event type tag code <br /> |
| `str` | `String`: A value to log <br />       |

|                  Returns                  ||
|-------|------------------------------------|
| `int` | The number of bytes written <br /> |

### writeEvent

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int writeEvent (int tag, 
                int value)
```

Record an event log message.

<br />

|                   Parameters                   ||
|---------|---------------------------------------|
| `tag`   | `int`: The event type tag code <br /> |
| `value` | `int`: A value to log <br />          |

|                  Returns                  ||
|-------|------------------------------------|
| `int` | The number of bytes written <br /> |

### writeEvent

Added in[API level 23](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int writeEvent (int tag, 
                float value)
```

Record an event log message.

<br />

|                   Parameters                   ||
|---------|---------------------------------------|
| `tag`   | `int`: The event type tag code <br /> |
| `value` | `float`: A value to log <br />        |

|                  Returns                  ||
|-------|------------------------------------|
| `int` | The number of bytes written <br /> |

### writeEvent

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int writeEvent (int tag, 
                Object... list)
```

Record an event log message.

<br />

|                    Parameters                    ||
|--------|------------------------------------------|
| `tag`  | `int`: The event type tag code <br />    |
| `list` | `Object`: A list of values to log <br /> |

|                  Returns                  ||
|-------|------------------------------------|
| `int` | The number of bytes written <br /> |

### writeEvent

Added in[API level 8](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

```
public static int writeEvent (int tag, 
                long value)
```

Record an event log message.

<br />

|                   Parameters                   ||
|---------|---------------------------------------|
| `tag`   | `int`: The event type tag code <br /> |
| `value` | `long`: A value to log <br />         |

|                  Returns                  ||
|-------|------------------------------------|
| `int` | The number of bytes written <br /> |