Module dagger

Package dagger.internal

Class Preconditions

java.lang.Object

dagger.internal.Preconditions

public final class Preconditions
extends java.lang.Object

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

Method Summary

Modifier and Type	Method	Description
static <T> void	checkBuilderRequirement(T requirement, java.lang.Class<T> clazz)	Checks that the component builder field requirement has been initialized.
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 <T> T	checkNotNull(T reference, java.lang.String errorMessageTemplate, java.lang.Object errorMessageArg)	Ensures that an object reference passed as a parameter to the calling method is not null.
static <T> T	checkNotNullFromComponent(T reference)	Ensures that an object reference returned from a component method is not null.
static <T> T	checkNotNullFromProvides(T reference)	Ensures that an object reference returned from a provides method is not null.

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

checkNotNullFromProvides

public static <T> T checkNotNullFromProvides(T reference)

Ensures that an object reference returned from a provides 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

checkNotNullFromComponent

public static <T> T checkNotNullFromComponent(T reference)

Ensures that an object reference returned from a component 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 errorMessageTemplate,
                                 java.lang.Object errorMessageArg)

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

Parameters:

reference - an object reference

errorMessageTemplate - a template for the exception message should the check fail. The message is formed by replacing the single %s placeholder in the template with errorMessageArg.

errorMessageArg - the argument to be substituted into the message template. Converted to a string using String.valueOf(Object), except for Class objects, which use Class.getCanonicalName().

Returns:

the non-null reference that was validated

Throws:

java.lang.NullPointerException - if reference is null

java.lang.IllegalArgumentException - if errorMessageTemplate doesn't contain exactly one "%s"

checkBuilderRequirement

public static <T> void checkBuilderRequirement(T requirement,
                                               java.lang.Class<T> clazz)

Checks that the component builder field requirement has been initialized.

Throws:

java.lang.IllegalStateException - if requirement is null