org.junit
Class Assert

java.lang.Object
  extended by org.junit.Assert

public class Assert
extends Object

A set of assertion methods useful for writing tests. Only failed assertions are recorded. These methods can be used directly: Assert.assertEquals(...), however, they read better if they are referenced through static import:

 import static org.junit.Assert.*;
    ...
    assertEquals(...);
 

Since:
4.0
See Also:
AssertionError

Constructor Summary
protected Assert()
          Protect constructor since it is a static only class
 
Method Summary
static void assertArrayEquals(byte[] expecteds, byte[] actuals)
          Asserts that two byte arrays are equal.
static void assertArrayEquals(char[] expecteds, char[] actuals)
          Asserts that two char arrays are equal.
static void assertArrayEquals(double[] expecteds, double[] actuals, double delta)
          Asserts that two double arrays are equal.
static void assertArrayEquals(float[] expecteds, float[] actuals, float delta)
          Asserts that two float arrays are equal.
static void assertArrayEquals(int[] expecteds, int[] actuals)
          Asserts that two int arrays are equal.
static void assertArrayEquals(long[] expecteds, long[] actuals)
          Asserts that two long arrays are equal.
static void assertArrayEquals(Object[] expecteds, Object[] actuals)
          Asserts that two object arrays are equal.
static void assertArrayEquals(short[] expecteds, short[] actuals)
          Asserts that two short arrays are equal.
static void assertArrayEquals(String message, byte[] expecteds, byte[] actuals)
          Asserts that two byte arrays are equal.
static void assertArrayEquals(String message, char[] expecteds, char[] actuals)
          Asserts that two char arrays are equal.
static void assertArrayEquals(String message, double[] expecteds, double[] actuals, double delta)
          Asserts that two double arrays are equal.
static void assertArrayEquals(String message, float[] expecteds, float[] actuals, float delta)
          Asserts that two float arrays are equal.
static void assertArrayEquals(String message, int[] expecteds, int[] actuals)
          Asserts that two int arrays are equal.
static void assertArrayEquals(String message, long[] expecteds, long[] actuals)
          Asserts that two long arrays are equal.
static void assertArrayEquals(String message, Object[] expecteds, Object[] actuals)
          Asserts that two object arrays are equal.
static void assertArrayEquals(String message, short[] expecteds, short[] actuals)
          Asserts that two short arrays are equal.
static void assertEquals(double expected, double actual)
          Deprecated. Use assertEquals(double expected, double actual, double delta) instead
static void assertEquals(double expected, double actual, double delta)
          Asserts that two doubles are equal to within a positive delta.
static void assertEquals(float expected, float actual, float delta)
          Asserts that two floats are equal to within a positive delta.
static void assertEquals(long expected, long actual)
          Asserts that two longs are equal.
static void assertEquals(Object[] expecteds, Object[] actuals)
          Deprecated. use assertArrayEquals
static void assertEquals(Object expected, Object actual)
          Asserts that two objects are equal.
static void assertEquals(String message, double expected, double actual)
          Deprecated. Use assertEquals(String message, double expected, double actual, double delta) instead
static void assertEquals(String message, double expected, double actual, double delta)
          Asserts that two doubles are equal to within a positive delta.
static void assertEquals(String message, float expected, float actual, float delta)
          Asserts that two floats are equal to within a positive delta.
static void assertEquals(String message, long expected, long actual)
          Asserts that two longs are equal.
static void assertEquals(String message, Object[] expecteds, Object[] actuals)
          Deprecated. use assertArrayEquals
static void assertEquals(String message, Object expected, Object actual)
          Asserts that two objects are equal.
static void assertFalse(boolean condition)
          Asserts that a condition is false.
static void assertFalse(String message, boolean condition)
          Asserts that a condition is false.
static void assertNotEquals(double first, double second, double delta)
          Asserts that two doubles or floats are not equal to within a positive delta.
static void assertNotEquals(long first, long second)
          Asserts that two longs are not equals.
static void assertNotEquals(Object first, Object second)
          Asserts that two objects are not equals.
static void assertNotEquals(String message, double first, double second, double delta)
          Asserts that two doubles or floats are not equal to within a positive delta.
static void assertNotEquals(String message, long first, long second)
          Asserts that two longs are not equals.
static void assertNotEquals(String message, Object first, Object second)
          Asserts that two objects are not equals.
static void assertNotNull(Object object)
          Asserts that an object isn't null.
static void assertNotNull(String message, Object object)
          Asserts that an object isn't null.
static void assertNotSame(Object unexpected, Object actual)
          Asserts that two objects do not refer to the same object.
static void assertNotSame(String message, Object unexpected, Object actual)
          Asserts that two objects do not refer to the same object.
static void assertNull(Object object)
          Asserts that an object is null.
static void assertNull(String message, Object object)
          Asserts that an object is null.
static void assertSame(Object expected, Object actual)
          Asserts that two objects refer to the same object.
static void assertSame(String message, Object expected, Object actual)
          Asserts that two objects refer to the same object.
static
<T> void
assertThat(String reason, T actual, Matcher<? super T> matcher)
          Asserts that actual satisfies the condition specified by matcher.
static
<T> void
assertThat(T actual, Matcher<? super T> matcher)
          Asserts that actual satisfies the condition specified by matcher.
static void assertTrue(boolean condition)
          Asserts that a condition is true.
static void assertTrue(String message, boolean condition)
          Asserts that a condition is true.
static void fail()
          Fails a test with no message.
static void fail(String message)
          Fails a test with the given message.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Assert

protected Assert()
Protect constructor since it is a static only class

Method Detail

assertTrue

public static void assertTrue(String message,
                              boolean condition)
Asserts that a condition is true. If it isn't it throws an AssertionError with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
condition - condition to be checked

assertTrue

public static void assertTrue(boolean condition)
Asserts that a condition is true. If it isn't it throws an AssertionError without a message.

Parameters:
condition - condition to be checked

assertFalse

public static void assertFalse(String message,
                               boolean condition)
Asserts that a condition is false. If it isn't it throws an AssertionError with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
condition - condition to be checked

assertFalse

public static void assertFalse(boolean condition)
Asserts that a condition is false. If it isn't it throws an AssertionError without a message.

Parameters:
condition - condition to be checked

fail

public static void fail(String message)
Fails a test with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
See Also:
AssertionError

fail

public static void fail()
Fails a test with no message.


assertEquals

public static void assertEquals(String message,
                                Object expected,
                                Object actual)
Asserts that two objects are equal. If they are not, an AssertionError is thrown with the given message. If expected and actual are null, they are considered equal.

Parameters:
message - the identifying message for the AssertionError (null okay)
expected - expected value
actual - actual value

assertEquals

public static void assertEquals(Object expected,
                                Object actual)
Asserts that two objects are equal. If they are not, an AssertionError without a message is thrown. If expected and actual are null, they are considered equal.

Parameters:
expected - expected value
actual - the value to check against expected

assertNotEquals

public static void assertNotEquals(String message,
                                   Object first,
                                   Object second)
Asserts that two objects are not equals. If they are, an AssertionError is thrown with the given message. If first and second are null, they are considered equal.

Parameters:
message - the identifying message for the AssertionError (null okay)
first - first value to check
second - the value to check against first

assertNotEquals

public static void assertNotEquals(Object first,
                                   Object second)
Asserts that two objects are not equals. If they are, an AssertionError without a message is thrown. If first and second are null, they are considered equal.

Parameters:
first - first value to check
second - the value to check against first

assertNotEquals

public static void assertNotEquals(String message,
                                   long first,
                                   long second)
Asserts that two longs are not equals. If they are, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
first - first value to check
second - the value to check against first

assertNotEquals

public static void assertNotEquals(long first,
                                   long second)
Asserts that two longs are not equals. If they are, an AssertionError without a message is thrown.

Parameters:
first - first value to check
second - the value to check against first

assertNotEquals

public static void assertNotEquals(String message,
                                   double first,
                                   double second,
                                   double delta)
Asserts that two doubles or floats are not equal to within a positive delta. If they are, an AssertionError is thrown with the given message. If the expected value is infinity then the delta value is ignored. NaNs are considered equal: assertNotEquals(Double.NaN, Double.NaN, *) fails

Parameters:
message - the identifying message for the AssertionError (null okay)
first - first value to check
second - the value to check against first
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertNotEquals

public static void assertNotEquals(double first,
                                   double second,
                                   double delta)
Asserts that two doubles or floats are not equal to within a positive delta. If they are, an AssertionError is thrown. If the expected value is infinity then the delta value is ignored.NaNs are considered equal: assertNotEquals(Double.NaN, Double.NaN, *) fails

Parameters:
first - first value to check
second - the value to check against first
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertArrayEquals

public static void assertArrayEquals(String message,
                                     Object[] expecteds,
                                     Object[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two object arrays are equal. If they are not, an AssertionError is thrown with the given message. If expecteds and actuals are null, they are considered equal.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - Object array or array of arrays (multi-dimensional array) with expected values.
actuals - Object array or array of arrays (multi-dimensional array) with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(Object[] expecteds,
                                     Object[] actuals)
Asserts that two object arrays are equal. If they are not, an AssertionError is thrown. If expected and actual are null, they are considered equal.

Parameters:
expecteds - Object array or array of arrays (multi-dimensional array) with expected values
actuals - Object array or array of arrays (multi-dimensional array) with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     byte[] expecteds,
                                     byte[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two byte arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - byte array with expected values.
actuals - byte array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(byte[] expecteds,
                                     byte[] actuals)
Asserts that two byte arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - byte array with expected values.
actuals - byte array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     char[] expecteds,
                                     char[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two char arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - char array with expected values.
actuals - char array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(char[] expecteds,
                                     char[] actuals)
Asserts that two char arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - char array with expected values.
actuals - char array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     short[] expecteds,
                                     short[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two short arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - short array with expected values.
actuals - short array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(short[] expecteds,
                                     short[] actuals)
Asserts that two short arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - short array with expected values.
actuals - short array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     int[] expecteds,
                                     int[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two int arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - int array with expected values.
actuals - int array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(int[] expecteds,
                                     int[] actuals)
Asserts that two int arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - int array with expected values.
actuals - int array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     long[] expecteds,
                                     long[] actuals)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two long arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - long array with expected values.
actuals - long array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(long[] expecteds,
                                     long[] actuals)
Asserts that two long arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - long array with expected values.
actuals - long array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     double[] expecteds,
                                     double[] actuals,
                                     double delta)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two double arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - double array with expected values.
actuals - double array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(double[] expecteds,
                                     double[] actuals,
                                     double delta)
Asserts that two double arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - double array with expected values.
actuals - double array with actual values

assertArrayEquals

public static void assertArrayEquals(String message,
                                     float[] expecteds,
                                     float[] actuals,
                                     float delta)
                              throws org.junit.internal.ArrayComparisonFailure
Asserts that two float arrays are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - float array with expected values.
actuals - float array with actual values
Throws:
org.junit.internal.ArrayComparisonFailure

assertArrayEquals

public static void assertArrayEquals(float[] expecteds,
                                     float[] actuals,
                                     float delta)
Asserts that two float arrays are equal. If they are not, an AssertionError is thrown.

Parameters:
expecteds - float array with expected values.
actuals - float array with actual values

assertEquals

public static void assertEquals(String message,
                                double expected,
                                double actual,
                                double delta)
Asserts that two doubles are equal to within a positive delta. If they are not, an AssertionError is thrown with the given message. If the expected value is infinity then the delta value is ignored. NaNs are considered equal: assertEquals(Double.NaN, Double.NaN, *) passes

Parameters:
message - the identifying message for the AssertionError (null okay)
expected - expected value
actual - the value to check against expected
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertEquals

public static void assertEquals(String message,
                                float expected,
                                float actual,
                                float delta)
Asserts that two floats are equal to within a positive delta. If they are not, an AssertionError is thrown with the given message. If the expected value is infinity then the delta value is ignored. NaNs are considered equal: assertEquals(Float.NaN, Float.NaN, *) passes

Parameters:
message - the identifying message for the AssertionError (null okay)
expected - expected value
actual - the value to check against expected
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertEquals

public static void assertEquals(long expected,
                                long actual)
Asserts that two longs are equal. If they are not, an AssertionError is thrown.

Parameters:
expected - expected long value.
actual - actual long value

assertEquals

public static void assertEquals(String message,
                                long expected,
                                long actual)
Asserts that two longs are equal. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expected - long expected value.
actual - long actual value

assertEquals

@Deprecated
public static void assertEquals(double expected,
                                           double actual)
Deprecated. Use assertEquals(double expected, double actual, double delta) instead


assertEquals

@Deprecated
public static void assertEquals(String message,
                                           double expected,
                                           double actual)
Deprecated. Use assertEquals(String message, double expected, double actual, double delta) instead


assertEquals

public static void assertEquals(double expected,
                                double actual,
                                double delta)
Asserts that two doubles are equal to within a positive delta. If they are not, an AssertionError is thrown. If the expected value is infinity then the delta value is ignored.NaNs are considered equal: assertEquals(Double.NaN, Double.NaN, *) passes

Parameters:
expected - expected value
actual - the value to check against expected
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertEquals

public static void assertEquals(float expected,
                                float actual,
                                float delta)
Asserts that two floats are equal to within a positive delta. If they are not, an AssertionError is thrown. If the expected value is infinity then the delta value is ignored. NaNs are considered equal: assertEquals(Float.NaN, Float.NaN, *) passes

Parameters:
expected - expected value
actual - the value to check against expected
delta - the maximum delta between expected and actual for which both numbers are still considered equal.

assertNotNull

public static void assertNotNull(String message,
                                 Object object)
Asserts that an object isn't null. If it is an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
object - Object to check or null

assertNotNull

public static void assertNotNull(Object object)
Asserts that an object isn't null. If it is an AssertionError is thrown.

Parameters:
object - Object to check or null

assertNull

public static void assertNull(String message,
                              Object object)
Asserts that an object is null. If it is not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
object - Object to check or null

assertNull

public static void assertNull(Object object)
Asserts that an object is null. If it isn't an AssertionError is thrown.

Parameters:
object - Object to check or null

assertSame

public static void assertSame(String message,
                              Object expected,
                              Object actual)
Asserts that two objects refer to the same object. If they are not, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
expected - the expected object
actual - the object to compare to expected

assertSame

public static void assertSame(Object expected,
                              Object actual)
Asserts that two objects refer to the same object. If they are not the same, an AssertionError without a message is thrown.

Parameters:
expected - the expected object
actual - the object to compare to expected

assertNotSame

public static void assertNotSame(String message,
                                 Object unexpected,
                                 Object actual)
Asserts that two objects do not refer to the same object. If they do refer to the same object, an AssertionError is thrown with the given message.

Parameters:
message - the identifying message for the AssertionError (null okay)
unexpected - the object you don't expect
actual - the object to compare to unexpected

assertNotSame

public static void assertNotSame(Object unexpected,
                                 Object actual)
Asserts that two objects do not refer to the same object. If they do refer to the same object, an AssertionError without a message is thrown.

Parameters:
unexpected - the object you don't expect
actual - the object to compare to unexpected

assertEquals

@Deprecated
public static void assertEquals(String message,
                                           Object[] expecteds,
                                           Object[] actuals)
Deprecated. use assertArrayEquals

Asserts that two object arrays are equal. If they are not, an AssertionError is thrown with the given message. If expecteds and actuals are null, they are considered equal.

Parameters:
message - the identifying message for the AssertionError (null okay)
expecteds - Object array or array of arrays (multi-dimensional array) with expected values.
actuals - Object array or array of arrays (multi-dimensional array) with actual values

assertEquals

@Deprecated
public static void assertEquals(Object[] expecteds,
                                           Object[] actuals)
Deprecated. use assertArrayEquals

Asserts that two object arrays are equal. If they are not, an AssertionError is thrown. If expected and actual are null, they are considered equal.

Parameters:
expecteds - Object array or array of arrays (multi-dimensional array) with expected values
actuals - Object array or array of arrays (multi-dimensional array) with actual values

assertThat

public static <T> void assertThat(T actual,
                                  Matcher<? super T> matcher)
Asserts that actual satisfies the condition specified by matcher. If not, an AssertionError is thrown with information about the matcher and failing value. Example:
   assertThat(0, is(1)); // fails:
     // failure message:
     // expected: is <1>
     // got value: <0>
   assertThat(0, is(not(1))) // passes
 
org.hamcrest.Matcher does not currently document the meaning of its type parameter T. This method assumes that a matcher typed as Matcher<T> can be meaningfully applied only to values that could be assigned to a variable of type T.

Type Parameters:
T - the static type accepted by the matcher (this can flag obvious compile-time problems such as assertThat(1, is("a"))
Parameters:
actual - the computed value being compared
matcher - an expression, built of Matchers, specifying allowed values
See Also:
CoreMatchers, MatcherAssert

assertThat

public static <T> void assertThat(String reason,
                                  T actual,
                                  Matcher<? super T> matcher)
Asserts that actual satisfies the condition specified by matcher. If not, an AssertionError is thrown with the reason and information about the matcher and failing value. Example:
   assertThat("Help! Integers don't work", 0, is(1)); // fails:
     // failure message:
     // Help! Integers don't work
     // expected: is <1>
     // got value: <0>
   assertThat("Zero is one", 0, is(not(1))) // passes
 
org.hamcrest.Matcher does not currently document the meaning of its type parameter T. This method assumes that a matcher typed as Matcher<T> can be meaningfully applied only to values that could be assigned to a variable of type T.

Type Parameters:
T - the static type accepted by the matcher (this can flag obvious compile-time problems such as assertThat(1, is("a"))
Parameters:
reason - additional information about the error
actual - the computed value being compared
matcher - an expression, built of Matchers, specifying allowed values
See Also:
CoreMatchers, MatcherAssert