1 // Copyright 2010 Google Inc. All Rights Reserved. 2 3 package org.junit.runners.model; 4 5 import java.util.ArrayList; 6 import java.util.Collections; 7 import java.util.List; 8 9 /** 10 * Collects multiple {@code Throwable}s into one exception. 11 */ 12 public class MultipleFailureException extends Exception { 13 private static final long serialVersionUID= 1L; 14 15 private final List<Throwable> fErrors; 16 17 public MultipleFailureException(List<Throwable> errors) { 18 fErrors= new ArrayList<Throwable>(errors); 19 } 20 21 public List<Throwable> getFailures() { 22 return Collections.unmodifiableList(fErrors); 23 } 24 25 @Override 26 public String getMessage() { 27 StringBuilder sb = new StringBuilder( 28 String.format("There were %d errors:", fErrors.size())); 29 for (Throwable e : fErrors) { 30 sb.append(String.format("\n %s(%s)", e.getClass().getName(), e.getMessage())); 31 } 32 return sb.toString(); 33 } 34 35 /** 36 * Asserts that a list of throwables is empty. If it isn't empty, 37 * will throw {@link MultipleFailureException} (if there are 38 * multiple throwables in the list) or the first element in the list 39 * (if there is only one element). 40 * 41 * @param errors list to check 42 * @throws Throwable if the list is not empty 43 */ 44 @SuppressWarnings("deprecation") 45 public static void assertEmpty(List<Throwable> errors) throws Throwable { 46 if (errors.isEmpty()) 47 return; 48 if (errors.size() == 1) 49 throw errors.get(0); 50 51 /* 52 * Many places in the code are documented to throw 53 * org.junit.internal.runners.model.MultipleFailureException. 54 * That class now extends this one, so we throw the internal 55 * exception in case developers have tests that catch 56 * MultipleFailureException. 57 */ 58 throw new org.junit.internal.runners.model.MultipleFailureException(errors); 59 } 60 } 61
