org.apache.flink.cdc.common.utils

类 Preconditions

java.lang.Object

org.apache.flink.cdc.common.utils.Preconditions

public final class Preconditions
extends Object

A collection of static utility methods to validate input.

This class is modelled after Google Guava's Preconditions class, and partly takes code from that class. We add this code to the Flink CDC code base in order to reduce external dependencies.

构造器概要

构造器

构造器和说明
Preconditions()

方法概要

限定符和类型	方法和说明
static void	checkArgument(boolean condition) Checks the given boolean condition, and throws an IllegalArgumentException if the condition is not met (evaluates to false).
static void	checkArgument(boolean condition, String errorMessageTemplate, Object... errorMessageArgs) Checks the given boolean condition, and throws an IllegalArgumentException if the condition is not met (evaluates to false).
static <T> T	checkNotNull(T reference) Ensures that the given object reference is not null.
static <T> T	checkNotNull(T reference, String errorMessage) Ensures that the given object reference is not null.
static <T> T	checkNotNull(T reference, String errorMessageTemplate, Object... errorMessageArgs) Ensures that the given object reference is not null.
static void	checkState(boolean condition) Checks the given boolean condition, and throws an IllegalStateException if the condition is not met (evaluates to false).
static void	checkState(boolean condition, Object errorMessage) Checks the given boolean condition, and throws an IllegalStateException if the condition is not met (evaluates to false).

从类继承的方法 java.lang.Object

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

构造器详细资料

Preconditions

public Preconditions()

方法详细资料

checkNotNull

public static <T> T checkNotNull(@Nullable
                                 T reference)

Ensures that the given object reference is not null. Upon violation, a NullPointerException with no message is thrown.

参数:

reference - The object reference

返回:

The object reference itself (generically typed).

抛出:

NullPointerException - Thrown, if the passed reference was null.

checkNotNull

public static <T> T checkNotNull(@Nullable
                                 T reference,
                                 @Nullable
                                 String errorMessage)

Ensures that the given object reference is not null. Upon violation, a NullPointerException with the given message is thrown.

参数:

reference - The object reference

errorMessage - The message for the NullPointerException that is thrown if the check fails.

返回:

The object reference itself (generically typed).

抛出:

NullPointerException - Thrown, if the passed reference was null.

checkNotNull

public static <T> T checkNotNull(T reference,
                                 @Nullable
                                 String errorMessageTemplate,
                                 @Nullable
                                 Object... errorMessageArgs)

Ensures that the given object reference is not null. Upon violation, a NullPointerException with the given message is thrown.

The error message is constructed from a template and an arguments array, after a similar fashion as String.format(String, Object...), but supporting only %s as a placeholder.

参数:

reference - The object reference

errorMessageTemplate - The message template for the NullPointerException that is thrown if the check fails. The template substitutes its %s placeholders with the error message arguments.

errorMessageArgs - The arguments for the error message, to be inserted into the message template for the %s placeholders.

返回:

The object reference itself (generically typed).

抛出:

NullPointerException - Thrown, if the passed reference was null.

checkArgument

public static void checkArgument(boolean condition)

Checks the given boolean condition, and throws an IllegalArgumentException if the condition is not met (evaluates to false).

参数:

condition - The condition to check

抛出:

IllegalArgumentException - Thrown, if the condition is violated.

checkArgument

public static void checkArgument(boolean condition,
                                 @Nullable
                                 String errorMessageTemplate,
                                 @Nullable
                                 Object... errorMessageArgs)

Checks the given boolean condition, and throws an IllegalArgumentException if the condition is not met (evaluates to false).

参数:

condition - The condition to check

errorMessageTemplate - The message template for the IllegalArgumentException that is thrown if the check fails. The template substitutes its %s placeholders with the error message arguments.

errorMessageArgs - The arguments for the error message, to be inserted into the message template for the %s placeholders.

抛出:

IllegalArgumentException - Thrown, if the condition is violated.

checkState

public static void checkState(boolean condition)

Checks the given boolean condition, and throws an IllegalStateException if the condition is not met (evaluates to false).

参数:

condition - The condition to check

抛出:

IllegalStateException - Thrown, if the condition is violated.

checkState

public static void checkState(boolean condition,
                              @Nullable
                              Object errorMessage)

Checks the given boolean condition, and throws an IllegalStateException if the condition is not met (evaluates to false). The exception will have the given error message.

参数:

condition - The condition to check

errorMessage - The message for the IllegalStateException that is thrown if the check fails.

抛出:

IllegalStateException - Thrown, if the condition is violated.