com.github.antelopeframework.util.Precondition Maven / Gradle / Ivy
The newest version!
package com.github.antelopeframework.util;
import java.io.File;
import com.github.antelopeframework.text.format.MessageFormatter;
/**
* 参考自com.google.common.base.Preconditions.
*
* @author yangzhi
*/
public final class Precondition {
private Precondition() {}
/**
* Ensures the truth of an expression involving one or more parameters to
* the calling method.
*
* @param expression a boolean expression
* @throws IllegalArgumentException
* if {@code expression} is false
*/
public static void checkArgument(boolean expression) {
if (!expression) {
throw new IllegalArgumentException();
}
}
/**
* Ensures the truth of an expression involving one or more parameters to
* the calling method.
*
* @param expression
* a boolean expression
* @param errorMessage
* the exception message to use if the check fails; will be
* converted to a string using {@link String#valueOf(Object)}
* @throws IllegalArgumentException
* if {@code expression} is false
*/
public static void checkArgument(boolean expression, Object errorMessage) {
if (!expression) {
throw new IllegalArgumentException(String.valueOf(errorMessage));
}
}
/**
* Ensures the truth of an expression involving one or more parameters to
* the calling method.
*
* @param expression a boolean expression
* @param errorMessageTemplate
* a template for the exception message should the check fail.
* The message is formed by replacing each {@code %s} placeholder
* in the template with an argument. These are matched by
* position - the first {@code %s} gets
* {@code errorMessageArgs[0]}, etc. Unmatched arguments will be
* appended to the formatted message in square braces. Unmatched
* placeholders will be left as-is.
* @param errorMessageArgs
* the arguments to be substituted into the message template.
* Arguments are converted to strings using
* {@link String#valueOf(Object)}.
* @throws IllegalArgumentException
* if {@code expression} is false
* @throws NullPointerException
* if the check fails and either {@code errorMessageTemplate} or
* {@code errorMessageArgs} is null (don't let this happen)
*/
public static void checkArgument(boolean expression,
String errorMessageTemplate, Object... errorMessageArgs) {
if (!expression) {
throw new IllegalArgumentException(format(errorMessageTemplate, errorMessageArgs));
}
}
/**
* Ensures the truth of an expression involving the state of the calling instance, but not
* involving any parameters to the calling method.
*
* @param expression a boolean expression
* @throws IllegalStateException if {@code expression} is false
*/
public static void checkState(boolean expression) {
if (!expression) {
throw new IllegalStateException();
}
}
/**
* Ensures the truth of an expression involving the state of the calling instance, but not
* involving any parameters to the calling method.
*
* @param expression a boolean expression
* @param errorMessage the exception message to use if the check fails; will be converted to a
* string using {@link String#valueOf(Object)}
* @throws IllegalStateException if {@code expression} is false
*/
public static void checkState(boolean expression, Object errorMessage) {
if (!expression) {
throw new IllegalStateException(String.valueOf(errorMessage));
}
}
/**
* Ensures the truth of an expression involving the state of the calling
* instance, but not involving any parameters to the calling method.
*
* @param expression
* a boolean expression
* @param errorMessageTemplate
* a template for the exception message should the check fail.
* The message is formed by replacing each {@code %s} placeholder
* in the template with an argument. These are matched by
* position - the first {@code %s} gets
* {@code errorMessageArgs[0]}, etc. Unmatched arguments will be
* appended to the formatted message in square braces. Unmatched
* placeholders will be left as-is.
* @param errorMessageArgs
* the arguments to be substituted into the message template.
* Arguments are converted to strings using
* {@link String#valueOf(Object)}.
* @throws IllegalStateException
* if {@code expression} is false
* @throws NullPointerException
* if the check fails and either {@code errorMessageTemplate} or
* {@code errorMessageArgs} is null (don't let this happen)
*/
public static void checkState(boolean expression, String errorMessageTemplate, Object... errorMessageArgs) {
if (!expression) {
throw new IllegalStateException(format(errorMessageTemplate, errorMessageArgs));
}
}
/**
* Ensures that an object reference passed as a parameter to the calling
* method is not null.
*
* @param reference
* an object reference
* @return the non-null reference that was validated
* @throws NullPointerException
* if {@code reference} is null
*/
public static T checkNotNull(T reference) {
if (reference == null) {
throw new NullPointerException();
}
return reference;
}
/**
* Ensures that an object reference passed as a parameter to the calling
* method is not null.
*
* @param reference
* an object reference
* @param errorMessage
* the exception message to use if the check fails; will be
* converted to a string using {@link String#valueOf(Object)}
* @return the non-null reference that was validated
* @throws NullPointerException
* if {@code reference} is null
*/
public static T checkNotNull(T reference, Object errorMessage) {
if (reference == null) {
throw new NullPointerException(String.valueOf(errorMessage));
}
return reference;
}
/**
* Ensures that an object reference passed as a parameter to the calling
* method is not null.
*
* @param reference
* an object reference
* @param errorMessageTemplate
* a template for the exception message should the check fail.
* The message is formed by replacing each {@code %s} placeholder
* in the template with an argument. These are matched by
* position - the first {@code %s} gets
* {@code errorMessageArgs[0]}, etc. Unmatched arguments will be
* appended to the formatted message in square braces. Unmatched
* placeholders will be left as-is.
* @param errorMessageArgs
* the arguments to be substituted into the message template.
* Arguments are converted to strings using
* {@link String#valueOf(Object)}.
* @return the non-null reference that was validated
* @throws NullPointerException
* if {@code reference} is null
*/
public static T checkNotNull(T reference, String errorMessageTemplate, Object... errorMessageArgs) {
if (reference == null) {
// If either of these parameters is null, the right thing happens
// anyway
throw new NullPointerException(format(errorMessageTemplate, errorMessageArgs));
}
return reference;
}
private static String format(String errorMessageTemplate, Object... errorMessageArgs) {
return MessageFormatter.arrayFormat(errorMessageTemplate, errorMessageArgs).getMessage();
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy