Added in [API level 31](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Ctors](https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#pubctors) \| [Methods](https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#inhmethods)
# PackageIdentifier
*** ** * ** ***
`
public
class
PackageIdentifier
`
`
extends https://developer.android.com/reference/java/lang/Object
`
`
`
|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.app.appsearch.PackageIdentifier |
*** ** * ** ***
This class represents a uniquely identifiable package.
## Summary
| ### Public constructors ||
|---|---|
| ` https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#PackageIdentifier(java.lang.String,%20byte[])(https://developer.android.com/reference/java/lang/String packageName, byte[] sha256Certificate) ` Creates a unique identifier for a package. |
| ### Public methods ||
|---|---|
| ` boolean` | ` https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. |
| ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#getPackageName()() ` Returns the name for a package. |
| ` byte[]` | ` https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#getSha256Certificate()() ` Returns the SHA-256 certificate for a single-signer package. |
| ` int` | ` https://developer.android.com/reference/android/app/appsearch/PackageIdentifier#hashCode()() ` Returns a hash code value for the object. |
### 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*.
## Public constructors
### PackageIdentifier
Added in [API level 31](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public PackageIdentifier (String packageName,
byte[] sha256Certificate)
```
Creates a unique identifier for a package.
SHA-256 certificate digests for a signed application can be retrieved with the [apksigner tool](https://developer.android.com/studio/command-line/apksigner) that is part of the
Android SDK build tools. Use `apksigner verify --print-certs path/to/apk.apk` to
retrieve the SHA-256 certificate digest for the target application. Once retrieved, the
SHA-256 certificate digest should be converted to a `byte[]` by decoding it in base16:
```
new android.content.pm.Signature(outputDigest).toByteArray();
```
| Parameters ||
|---|---|
| `packageName` | `String`: Name of the package. This value cannot be `null`.
|
| `sha256Certificate` | `byte`: SHA-256 certificate digest of the package. This value cannot be `null`.
|
## Public methods
### equals
Added in [API level 31](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.
| Parameters ||
|---|---|
| `obj` | `Object`: This value may be `null`.
|
| Returns ||
|---|---|
| `boolean` | `true` if this object is the same as the obj argument; `false` otherwise.
|
### getPackageName
Added in [API level 31](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public String getPackageName ()
```
Returns the name for a package.
| Returns ||
|---|---|
| `https://developer.android.com/reference/java/lang/String` | This value cannot be `null`.
|
### getSha256Certificate
Added in [API level 31](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public byte[] getSha256Certificate ()
```
Returns the SHA-256 certificate for a single-signer package.
This method should not be called for multiple-signing certificates. Use
`https://developer.android.com/` to retrieve all certificates.
| Returns ||
|---|---|
| `byte[]` | This value cannot be `null`.
|
### hashCode
Added in [API level 31](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.
| Returns ||
|---|---|
| `int` | a hash code value for this object.
|