From 8f45918465c1c992d55fe08f2d7e49689b722b38 Mon Sep 17 00:00:00 2001
From: Stephen Colebourne
Characters will be chosen from the set of characters whose
- * ASCII value is between 32
and 127
.
32
and 126
(inclusive).
*
* @param count length of random string to create
* @return the random string
@@ -199,9 +200,8 @@ public class RandomStringUtils {
*
* This method has exactly the same semantics as {@link
* #random(int,int,int,boolean,boolean,char[],Random)}, but
- * instead of depending on internal source of randomness ({@link
- * #RANDOM}) it uses externally supplied instance of {@link
- * Random} class.
+ * instead of using an externally supplied source of randomness, it uses
+ * the internal static {@link Random} instance ({@link #RANDOM}).
*
* @param count length of random string to create
* @param start position in set of chars to start at
@@ -256,7 +256,7 @@ public class RandomStringUtils {
throw new IllegalArgumentException("Requested random string length " + count + " is less than 0.");
}
if( (start == 0) && (end == 0) ) {
- end = (int)'z';
+ end = (int)'z' + 1;
start = (int)' ';
if(!letters && !numbers) {
start = 0;
diff --git a/src/test/org/apache/commons/lang/RandomStringUtilsTest.java b/src/test/org/apache/commons/lang/RandomStringUtilsTest.java
index f6ff7c729..a9d03c720 100644
--- a/src/test/org/apache/commons/lang/RandomStringUtilsTest.java
+++ b/src/test/org/apache/commons/lang/RandomStringUtilsTest.java
@@ -57,12 +57,14 @@ import java.util.Random;
import junit.framework.*;
import junit.textui.TestRunner;
+
/**
* Unit tests {@link org.apache.commons.lang.RandomStringUtils}.
*
* @author Steven Caswell
* @author Ringo De Smet
- * @version $Id: RandomStringUtilsTest.java,v 1.6 2003/05/14 02:50:43 bayard Exp $
+ * @author Phil Steitz
+ * @version $Id: RandomStringUtilsTest.java,v 1.7 2003/06/09 21:36:03 scolebourne Exp $
*/
public class RandomStringUtilsTest extends junit.framework.TestCase {
/**
@@ -167,6 +169,99 @@ public class RandomStringUtilsTest extends junit.framework.TestCase {
assertNotNull("random(<0) throws exception", e);
}
+ /**
+ * Make sure boundary alphanumeric characters are generated by randomAlphaNumeric
+ * This test will fail randomly with probability = 6 * (61/62)**1000 ~ 5.2E-7
+ */
+ public void testRandomAlphaNumeric() {
+ char[] testChars = {'a', 'z', 'A', 'Z', '0', '9'};
+ boolean[] found = {false, false, false, false, false, false};
+ for (int i = 0; i < 100; i++) {
+ String randString = RandomStringUtils.randomAlphanumeric(10);
+ for (int j = 0; j < testChars.length; j++) {
+ if (randString.indexOf(testChars[j]) > 0) {
+ found[j] = true;
+ }
+ }
+ }
+ for (int i = 0; i < testChars.length; i++) {
+ if (!found[i]) {
+ fail("alphanumeric character not generated in 1000 attempts: "
+ + testChars[i] +" -- repeated failures indicate a problem ");
+ }
+ }
+ }
+
+ /**
+ * Make sure '0' and '9' are generated by randomNumeric
+ * This test will fail randomly with probability = 2 * (9/10)**1000 ~ 3.5E-46
+ */
+ public void testRandomNumeric() {
+ char[] testChars = {'0','9'};
+ boolean[] found = {false, false};
+ for (int i = 0; i < 100; i++) {
+ String randString = RandomStringUtils.randomNumeric(10);
+ for (int j = 0; j < testChars.length; j++) {
+ if (randString.indexOf(testChars[j]) > 0) {
+ found[j] = true;
+ }
+ }
+ }
+ for (int i = 0; i < testChars.length; i++) {
+ if (!found[i]) {
+ fail("digit not generated in 1000 attempts: "
+ + testChars[i] +" -- repeated failures indicate a problem ");
+ }
+ }
+ }
+
+ /**
+ * Make sure boundary alpha characters are generated by randomAlphabetic
+ * This test will fail randomly with probability = 4 * (51/52)**1000 ~ 1.58E-8
+ */
+ public void testRandomAlphabetic() {
+ char[] testChars = {'a', 'z', 'A', 'Z'};
+ boolean[] found = {false, false, false, false};
+ for (int i = 0; i < 100; i++) {
+ String randString = RandomStringUtils.randomAlphabetic(10);
+ for (int j = 0; j < testChars.length; j++) {
+ if (randString.indexOf(testChars[j]) > 0) {
+ found[j] = true;
+ }
+ }
+ }
+ for (int i = 0; i < testChars.length; i++) {
+ if (!found[i]) {
+ fail("alphanumeric character not generated in 1000 attempts: "
+ + testChars[i] +" -- repeated failures indicate a problem ");
+ }
+ }
+ }
+
+ /**
+ * Make sure 32 and 127 are generated by randomNumeric
+ * This test will fail randomly with probability = 2*(95/96)**1000 ~ 5.7E-5
+ */
+ public void testRandomAscii() {
+ char[] testChars = {(char) 32, (char) 126};
+ boolean[] found = {false, false};
+ for (int i = 0; i < 100; i++) {
+ String randString = RandomStringUtils.randomAscii(10);
+ for (int j = 0; j < testChars.length; j++) {
+ if (randString.indexOf(testChars[j]) > 0) {
+ found[j] = true;
+ }
+ }
+ }
+ for (int i = 0; i < testChars.length; i++) {
+ if (!found[i]) {
+ fail("ascii character not generated in 1000 attempts: "
+ + (int) testChars[i] +
+ " -- repeated failures indicate a problem");
+ }
+ }
+ }
+
/**
* Test homogeneity of random strings generated --
* i.e., test that characters show up with expected frequencies
@@ -195,8 +290,6 @@ public class RandomStringUtilsTest extends junit.framework.TestCase {
chiSquare(expected,counts) < 13.82);
}
- //FIXME: add similar tests for other functions
-
/**
* Computes Chi-Square statistic given observed and expected counts
* @param observed array of observed frequency counts
diff --git a/src/test/org/apache/commons/lang/math/RandomUtilsTest.java b/src/test/org/apache/commons/lang/math/RandomUtilsTest.java
index dab76bba6..bad8bd670 100644
--- a/src/test/org/apache/commons/lang/math/RandomUtilsTest.java
+++ b/src/test/org/apache/commons/lang/math/RandomUtilsTest.java
@@ -63,7 +63,7 @@ import junit.framework.TestSuite;
* Test cases for the {@link RandomUtils} class.
*
* @author Phil Steitz
- * @version $Revision: 1.2 $ $Date: 2003/06/08 14:19:43 $
+ * @version $Revision: 1.3 $ $Date: 2003/06/09 21:36:03 $
*/
public final class RandomUtilsTest extends TestCase {
@@ -126,12 +126,12 @@ public final class RandomUtilsTest extends TestCase {
assertTrue(result >= 0);
observed[result]++;
}
- /* Use ChiSquare dist with df = 4-1 = 3, alpha = .01
- * Change to 16.27 for alpha = .001
+ /* Use ChiSquare dist with df = 4-1 = 3, alpha = .001
+ * Change to 11.34 for alpha = .01
*/
assertTrue(
- "chi-square test -- will fail about 1 in 100 times",
- chiSquare(expected,observed) < 11.34);
+ "chi-square test -- will fail about 1 in 1000 times",
+ chiSquare(expected,observed) < 16.27);
}
/** test distribution of nextLong() */
@@ -171,12 +171,12 @@ public final class RandomUtilsTest extends TestCase {
observed[1]++;
}
}
- /* Use ChiSquare dist with df = 2-1 = 1, alpha = .01
- * Change to 10.83 for alpha = .001
+ /* Use ChiSquare dist with df = 2-1 = 1, alpha = .001
+ * Change to 6.64 for alpha = .01
*/
assertTrue(
- "chi-square test -- will fail about 1 in 100 times",
- chiSquare(expected,observed) < 6.64);
+ "chi-square test -- will fail about 1 in 1000 times",
+ chiSquare(expected,observed) < 10.83);
}
@@ -214,12 +214,12 @@ public final class RandomUtilsTest extends TestCase {
observed[1]++;
}
}
- /* Use ChiSquare dist with df = 2-1 = 1, alpha = .01
- * Change to 10.83 for alpha = .001
+ /* Use ChiSquare dist with df = 2-1 = 1, alpha = .001
+ * Change to 6.64 for alpha = .01
*/
assertTrue(
- "chi-square test -- will fail about 1 in 100 times",
- chiSquare(expected,observed) < 6.64);
+ "chi-square test -- will fail about 1 in 1000 times",
+ chiSquare(expected,observed) < 10.83 );
}
/** test distribution of nextFloat() */
@@ -256,12 +256,12 @@ public final class RandomUtilsTest extends TestCase {
observed[1]++;
}
}
- /* Use ChiSquare dist with df = 2-1 = 1, alpha = .01
- * Change to 10.83 for alpha = .001
+ /* Use ChiSquare dist with df = 2-1 = 1, alpha = .001
+ * Change to 6.64 for alpha = .01
*/
assertTrue(
- "chi-square test -- will fail about 1 in 100 times",
- chiSquare(expected,observed) < 6.64);
+ "chi-square test -- will fail about 1 in 1000 times",
+ chiSquare(expected,observed) < 10.83);
}
/** test distribution of nextDouble() */
@@ -298,12 +298,12 @@ public final class RandomUtilsTest extends TestCase {
observed[1]++;
}
}
- /* Use ChiSquare dist with df = 2-1 = 1, alpha = .01
- * Change to 10.83 for alpha = .001
+ /* Use ChiSquare dist with df = 2-1 = 1, alpha = .001
+ * Change to 6.64 for alpha = .01
*/
assertTrue(
- "chi-square test -- will fail about 1 in 100 times",
- chiSquare(expected,observed) < 6.64);
+ "chi-square test -- will fail about 1 in 1000 times",
+ chiSquare(expected,observed) < 10.83);
}
/** make sure that setSeed fails */