com.oracle.bedrock.matchers.ThrowableCausedByMatcher Maven / Gradle / Ivy
/*
* File: ThrowableCausedByMatcher.java
*
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* the Common Development and Distribution License 1.0 (the "License").
*
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package com.oracle.bedrock.matchers;
import org.hamcrest.Description;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeMatcher;
/**
* A {@link TypeSafeMatcher} for matching one of the {@link Throwable#getCause()} {@link Throwable}s.
*
* Copyright (c) 2016. All Rights Reserved. Oracle Corporation.
* Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
*
* @author Brian Oliver
*/
public class ThrowableCausedByMatcher extends TypeSafeMatcher
{
/**
* The {@link Matcher} for the {@link Throwable} message.
*/
private Matcher matcher;
/**
* Constructs a {@link ThrowableCausedByMatcher} given a {@link Matcher} for the
* {@link Throwable#getCause()} method.
*
* @param matcher the message {@link Matcher}
*/
private ThrowableCausedByMatcher(Matcher matcher)
{
this.matcher = matcher;
}
/**
* Constructs a {@link ThrowableCausedByMatcher} for a {@link Throwable#getCause()}
* matching the specified {@link Matcher}.
*
* @param matcher the message {@link Matcher}
* @param the type of {@link Throwable}
*
* @return a {@link ThrowableCausedByMatcher}
*/
public static ThrowableCausedByMatcher causedBy(Matcher matcher)
{
return new ThrowableCausedByMatcher<>(matcher);
}
@Override
protected boolean matchesSafely(T t)
{
Throwable throwable = t;
// ensure that one of the causes of the throwable matches
while (throwable != null)
{
if (matcher.matches(throwable.getCause()))
{
return true;
}
else
{
throwable = throwable.getCause();
}
}
// nothing matched
return false;
}
@Override
public void describeTo(Description description)
{
description.appendText("throwable caused by ");
matcher.describeTo(description);
}
}