com.google.android.exoplayer.util

Class Assertions

java.lang.Object

com.google.android.exoplayer.util.Assertions

public final class Assertions
extends Object

Provides methods for asserting the truth of expressions and properties.

Method Summary

Modifier and Type	Method and Description
static void	checkArgument(boolean expression) Ensures the truth of an expression involving one or more arguments passed to the calling method.
static void	checkArgument(boolean expression, Object errorMessage) Ensures the truth of an expression involving one or more arguments passed to the calling method.
static void	checkMainThread() Ensures that the calling thread is the application's main thread.
static String	checkNotEmpty(String string) Ensures that a string passed as an argument to the calling method is not null or 0-length.
static String	checkNotEmpty(String string, Object errorMessage) Ensures that a string passed as an argument to the calling method is not null or 0-length.
static <T> T	checkNotNull(T reference) Ensures that an object reference is not null.
static <T> T	checkNotNull(T reference, Object errorMessage) Ensures that an object reference is not null.
static void	checkState(boolean expression) Ensures the truth of an expression involving the state of the calling instance.
static void	checkState(boolean expression, Object errorMessage) Ensures the truth of an expression involving the state of the calling instance.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

checkArgument

public static void checkArgument(boolean expression)

Ensures the truth of an expression involving one or more arguments passed to the calling method.

Parameters:

expression - A boolean expression.

Throws:

IllegalArgumentException - If expression is false.

checkArgument

public static void checkArgument(boolean expression,
                                 Object errorMessage)

Ensures the truth of an expression involving one or more arguments passed to the calling method.

Parameters:

expression - A boolean expression.

errorMessage - The exception message to use if the check fails. The message is converted to a String using String.valueOf(Object).

Throws:

IllegalArgumentException - If expression is false.

checkState

public static void checkState(boolean expression)

Ensures the truth of an expression involving the state of the calling instance.

Parameters:

expression - A boolean expression.

Throws:

IllegalStateException - If expression is false.

checkState

public static void checkState(boolean expression,
                              Object errorMessage)

Ensures the truth of an expression involving the state of the calling instance.

Parameters:

expression - A boolean expression.

errorMessage - The exception message to use if the check fails. The message is converted to a string using String.valueOf(Object).

Throws:

IllegalStateException - If expression is false.

checkNotNull

public static <T> T checkNotNull(T reference)

Ensures that an object reference is not null.

Parameters:

reference - An object reference.

Returns:

The non-null reference that was validated.

Throws:

NullPointerException - If reference is null.

checkNotNull

public static <T> T checkNotNull(T reference,
                                 Object errorMessage)

Ensures that an object reference is not null.

Parameters:

reference - An object reference.

errorMessage - The exception message to use if the check fails. The message is converted to a string using String.valueOf(Object).

Returns:

The non-null reference that was validated.

Throws:

NullPointerException - If reference is null.

checkNotEmpty

public static String checkNotEmpty(String string)

Ensures that a string passed as an argument to the calling method is not null or 0-length.

Parameters:

string - A string.

Returns:

The non-null, non-empty string that was validated.

Throws:

IllegalArgumentException - If string is null or 0-length.

checkNotEmpty

public static String checkNotEmpty(String string,
                                   Object errorMessage)

Ensures that a string passed as an argument to the calling method is not null or 0-length.

Parameters:

string - A string.

errorMessage - The exception message to use if the check fails. The message is converted to a string using String.valueOf(Object).

Returns:

The non-null, non-empty string that was validated.

Throws:

IllegalArgumentException - If string is null or 0-length.

checkMainThread

public static void checkMainThread()

Ensures that the calling thread is the application's main thread.

Throws:

IllegalStateException - If the calling thread is not the application's main thread.