com.nytimes.android.external.cache

Class Preconditions

java.lang.Object

com.nytimes.android.external.cache.Preconditions

public final class Preconditions
extends java.lang.Object

An adaptation of Guava's com.google.common.base.Preconditions that is specially tailored to support checks applied in Dagger's generated code.

Method Summary

Modifier and Type	Method and Description
static void	checkArgument(boolean expression)
static void	checkArgument(boolean expression, java.lang.Object errorMessage) Ensures the truth of an expression involving one or more parameters to the calling method.
static void	checkArgument(boolean expression, java.lang.String errorMessageTemplate, java.lang.Object... errorMessageArgs) Ensures the truth of an expression involving one or more parameters to the calling method.
static <T> T	checkNotNull(T reference) Ensures that an object reference passed as a parameter to the calling method is not null.
static <T> T	checkNotNull(T reference, java.lang.String errorMessage) Ensures that an object reference passed as a parameter to the calling method is not null.
static void	checkState(boolean expression)
static void	checkState(boolean expression, java.lang.Object errorMessage) Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
static void	checkState(boolean expression, java.lang.String errorMessageTemplate, java.lang.Object... errorMessageArgs) Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Methods inherited from class java.lang.Object

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

Method Detail

checkNotNull

public static <T> T checkNotNull(T reference)

Ensures that an object reference passed as a parameter to the calling method is not null.

Parameters:

reference - an object reference

Returns:

the non-null reference that was validated

Throws:

java.lang.NullPointerException - if reference is null

checkNotNull

public static <T> T checkNotNull(T reference,
                                 java.lang.String errorMessage)

Ensures that an object reference passed as a parameter to the calling method is not null.

Parameters:

reference - an object reference

errorMessage - the exception message to use if the check fails

Returns:

the non-null reference that was validated

Throws:

java.lang.NullPointerException - if reference is null

checkArgument

public static void checkArgument(boolean expression)

checkArgument

public static void checkArgument(boolean expression,
                                 java.lang.Object errorMessage)

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

Parameters:

expression - a boolean expression

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

Throws:

java.lang.IllegalArgumentException - if expression is false

checkArgument

public static void checkArgument(boolean expression,
                                 java.lang.String errorMessageTemplate,
                                 java.lang.Object... errorMessageArgs)

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

Parameters:

expression - a boolean expression

errorMessageTemplate - a template for the exception message should the check fail. The message is formed by replacing each %s placeholder in the template with an argument. These are matched by position - the first %s gets errorMessageArgs[0], etc. Unmatched arguments will be appended to the formatted message in square braces. Unmatched placeholders will be left as-is.

errorMessageArgs - the arguments to be substituted into the message template. Arguments are converted to strings using String.valueOf(Object).

Throws:

java.lang.IllegalArgumentException - if expression is false

java.lang.NullPointerException - if the check fails and either errorMessageTemplate or errorMessageArgs is null (don't let this happen)

checkState

public static void checkState(boolean expression)

checkState

public static void checkState(boolean expression,
                              java.lang.Object errorMessage)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression

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

Throws:

java.lang.IllegalStateException - if expression is false

checkState

public static void checkState(boolean expression,
                              java.lang.String errorMessageTemplate,
                              java.lang.Object... errorMessageArgs)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression

errorMessageTemplate - a template for the exception message should the check fail. The message is formed by replacing each %s placeholder in the template with an argument. These are matched by position - the first %s gets errorMessageArgs[0], etc. Unmatched arguments will be appended to the formatted message in square braces. Unmatched placeholders will be left as-is.

errorMessageArgs - the arguments to be substituted into the message template. Arguments are converted to strings using String.valueOf(Object).

Throws:

java.lang.IllegalStateException - if expression is false

java.lang.NullPointerException - if the check fails and either errorMessageTemplate or errorMessageArgs is null (don't let this happen)