Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Inherited Constants](https://developer.android.com/reference/android/content/pm/Signature#inhconstants) \| [Fields](https://developer.android.com/reference/android/content/pm/Signature#lfields) \| [Ctors](https://developer.android.com/reference/android/content/pm/Signature#pubctors) \| [Methods](https://developer.android.com/reference/android/content/pm/Signature#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/android/content/pm/Signature#inhmethods)

# Signature

*** ** * ** ***

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


`
public


class
Signature
`


`

extends https://developer.android.com/reference/java/lang/Object


`

`


implements

https://developer.android.com/reference/android/os/Parcelable


`

|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.content.pm.Signature |

<br />

*** ** * ** ***

Opaque, immutable representation of a signing certificate associated with an
application package.


This class name is slightly misleading, since it's not actually a signature.

## Summary

| ### Inherited constants |
|---|
| From interface `https://developer.android.com/reference/android/os/Parcelable` |---|---| | `int` | `https://developer.android.com/reference/android/os/Parcelable#CONTENTS_FILE_DESCRIPTOR` Descriptor bit used with `https://developer.android.com/reference/android/os/Parcelable#describeContents()`: indicates that the Parcelable object's flattened representation includes a file descriptor. | | `int` | `https://developer.android.com/reference/android/os/Parcelable#PARCELABLE_WRITE_RETURN_VALUE` Flag for use with `https://developer.android.com/reference/android/os/Parcelable#writeToParcel(android.os.Parcel,%20int)`: the object being written is a return value, that is the result of a function such as "`Parcelable someFunction()`", "`void someFunction(out Parcelable)`", or "`void someFunction(inout Parcelable)`". | |

| ### Fields ||
|---|---|
| ` public static final https://developer.android.com/reference/android/os/Parcelable.Creator<https://developer.android.com/reference/android/content/pm/Signature>` | `https://developer.android.com/reference/android/content/pm/Signature#CREATOR` |

| ### Public constructors ||
|---|---|
| ` https://developer.android.com/reference/android/content/pm/Signature#Signature(byte[])(byte[] signature) ` Create Signature from an existing raw byte array. |
| ` https://developer.android.com/reference/android/content/pm/Signature#Signature(java.lang.String)(https://developer.android.com/reference/java/lang/String text) ` Create Signature from a text representation previously returned by `https://developer.android.com/reference/android/content/pm/Signature#toChars()` or `https://developer.android.com/reference/android/content/pm/Signature#toCharsString()`. |

| ### Public methods ||
|---|---|
| ` int` | ` https://developer.android.com/reference/android/content/pm/Signature#describeContents()() ` Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. |
| ` boolean` | ` https://developer.android.com/reference/android/content/pm/Signature#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. |
| ` int` | ` https://developer.android.com/reference/android/content/pm/Signature#hashCode()() ` Returns a hash code value for the object. |
| ` byte[]` | ` https://developer.android.com/reference/android/content/pm/Signature#toByteArray()() ` |
| ` char[]` | ` https://developer.android.com/reference/android/content/pm/Signature#toChars()() ` Encode the Signature as ASCII text. |
| ` char[]` | ` https://developer.android.com/reference/android/content/pm/Signature#toChars(char[],%20int[])(char[] existingArray, int[] outLen) ` Encode the Signature as ASCII text in to an existing array. |
| ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/android/content/pm/Signature#toCharsString()() ` Return the result of `https://developer.android.com/reference/android/content/pm/Signature#toChars()` as a String. |
| ` void` | ` https://developer.android.com/reference/android/content/pm/Signature#writeToParcel(android.os.Parcel,%20int)(https://developer.android.com/reference/android/os/Parcel dest, int parcelableFlags) ` Flatten this object in to a Parcel. |

| ### Inherited methods |
|---|---|
| From class ` https://developer.android.com/reference/java/lang/Object ` |---|---| | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/lang/Object#clone()() ` Creates and returns a copy of this object. | | ` boolean` | ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` 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 https://developer.android.com/reference/java/lang/Class<?>` | ` https://developer.android.com/reference/java/lang/Object#getClass()() ` Returns the runtime class of this `Object`. | | ` int` | ` https://developer.android.com/reference/java/lang/Object#hashCode()() ` Returns a hash code value for the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notify()() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notifyAll()() ` Wakes up all threads that are waiting on this object's monitor. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/lang/Object#toString()() ` Returns a string representation of the object. | | ` final void` | ` 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` | ` 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` | ` 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*. | ||
| From interface ` https://developer.android.com/reference/android/os/Parcelable ` |---|---| | ` abstract int` | ` https://developer.android.com/reference/android/os/Parcelable#describeContents()() ` Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. | | ` abstract void` | ` https://developer.android.com/reference/android/os/Parcelable#writeToParcel(android.os.Parcel,%20int)(https://developer.android.com/reference/android/os/Parcel dest, int flags) ` Flatten this object in to a Parcel. | ||

## Fields

### CREATOR

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public static final Creator<Signature> CREATOR
```

<br />

<br />

## Public constructors

### Signature

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public Signature (byte[] signature)
```

Create Signature from an existing raw byte array.

<br />

| Parameters ||
|---|---|
| `signature` | `byte` <br /> |

### Signature

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public Signature (String text)
```

Create Signature from a text representation previously returned by
`https://developer.android.com/reference/android/content/pm/Signature#toChars()` or `https://developer.android.com/reference/android/content/pm/Signature#toCharsString()`. Signatures are expected to
be a hex-encoded ASCII string.

<br />

| Parameters ||
|---|---|
| `text` | `String`: hex-encoded string representing the signature <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/IllegalArgumentException` | when signature is odd-length |

## Public methods

### describeContents

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public int describeContents ()
```

Describe the kinds of special objects contained in this Parcelable
instance's marshaled representation. For example, if the object will
include a file descriptor in the output of `https://developer.android.com/reference/android/os/Parcelable#writeToParcel(android.os.Parcel,%20int)`,
the return value of this method must include the
`https://developer.android.com/reference/android/os/Parcelable#CONTENTS_FILE_DESCRIPTOR` bit.

<br />

| Returns ||
|---|---|
| `int` | a bitmask indicating the set of special object types marshaled by this Parcelable object instance. Value is either `0` or - `https://developer.android.com/reference/android/os/Parcelable#CONTENTS_FILE_DESCRIPTOR` |

### equals

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public boolean equals (Object obj)
```

Indicates whether some other object is "equal to" this one.


The `equals` method implements an equivalence relation
on non-null object references:

- It is *reflexive*: for any non-null reference value `x`, `x.equals(x)` should return `true`.
- It is *symmetric*: for any non-null reference values `x` and `y`, `x.equals(y)` should return `true` if and only if `y.equals(x)` returns `true`.
- It is *transitive*: for any non-null reference values `x`, `y`, and `z`, if `x.equals(y)` returns `true` and `y.equals(z)` returns `true`, then `x.equals(z)` should return `true`.
- It is *consistent*: for any non-null reference values `x` and `y`, multiple invocations of `x.equals(y)` consistently return `true` or consistently return `false`, provided no information used in `equals` comparisons on the objects is modified.
- For any non-null reference value `x`, `x.equals(null)` should return `false`.


An equivalence relation partitions the elements it operates on
into *equivalence classes*; all the members of an
equivalence class are equal to each other. Members of an
equivalence class are substitutable for each other, at least
for some purposes.

<br />

| Parameters ||
|---|---|
| `obj` | `Object`: This value may be `null`. <br /> |

| Returns ||
|---|---|
| `boolean` | `true` if this object is the same as the obj argument; `false` otherwise. <br /> |

### hashCode

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public int hashCode ()
```

Returns a hash code value for the object. This method is
supported for the benefit of hash tables such as those provided by
`https://developer.android.com/reference/java/util/HashMap`.


The general contract of `hashCode` is:

- Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
- If two objects are equal according to the `https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)` method, then calling the `hashCode` method on each of the two objects must produce the same integer result.
- It is *not* required that if two objects are unequal according to the `https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

<br />

<br />

| Returns ||
|---|---|
| `int` | a hash code value for this object. <br /> |

### toByteArray

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public byte[] toByteArray ()
```

<br />

<br />

| Returns ||
|---|---|
| `byte[]` | the contents of this signature as a byte array. <br /> |

### toChars

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public char[] toChars ()
```

Encode the Signature as ASCII text.

<br />

| Returns ||
|---|---|
| `char[]` | <br /> |

### toChars

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public char[] toChars (char[] existingArray, 
                int[] outLen)
```

Encode the Signature as ASCII text in to an existing array.

<br />

| Parameters ||
|---|---|
| `existingArray` | `char`: Existing char array or null. <br /> |
| `outLen` | `int`: Output parameter for the number of characters written in to the array. <br /> |

| Returns ||
|---|---|
| `char[]` | Returns either <var translate="no">existingArray</var> if it was large enough to hold the ASCII representation, or a newly created char\[\] array if needed. <br /> |

### toCharsString

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public String toCharsString ()
```

Return the result of `https://developer.android.com/reference/android/content/pm/Signature#toChars()` as a String.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/lang/String` | <br /> |

### writeToParcel

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public void writeToParcel (Parcel dest, 
                int parcelableFlags)
```

Flatten this object in to a Parcel.

<br />

| Parameters ||
|---|---|
| `dest` | `Parcel`: The Parcel in which the object should be written. This value cannot be `null`. <br /> |
| `parcelableFlags` | `int`: Additional flags about how the object should be written. May be 0 or `https://developer.android.com/reference/android/os/Parcelable#PARCELABLE_WRITE_RETURN_VALUE`. Value is either `0` or a combination of the following: - `https://developer.android.com/reference/android/os/Parcelable#PARCELABLE_WRITE_RETURN_VALUE` |