contains instead of indexof
diff --git a/src/test/java/org/apache/easyant/core/EasyAntBaseTest.java b/src/test/java/org/apache/easyant/core/EasyAntBaseTest.java
index 3e1495a..d4587be 100755
--- a/src/test/java/org/apache/easyant/core/EasyAntBaseTest.java
+++ b/src/test/java/org/apache/easyant/core/EasyAntBaseTest.java
@@ -127,7 +127,7 @@
     public void assertLogContaining(String substring) {
         String realLog = getLog();
         assertTrue("expecting log to contain \"" + substring + "\" log was \"" + realLog + "\"",
-                realLog.indexOf(substring) >= 0);
+                realLog.contains(substring));
     }
 
     /**
@@ -136,7 +136,7 @@
     public void assertLogNotContaining(String substring) {
         String realLog = getLog();
         assertFalse("didn't expect log to contain \"" + substring + "\" log was \"" + realLog + "\"",
-                realLog.indexOf(substring) >= 0);
+                realLog.contains(substring));
     }
 
     /**
@@ -159,7 +159,7 @@
         String realOutput = getOutput();
         String realMessage = (message != null) ? message : "expecting output to contain \"" + substring
                 + "\" output was \"" + realOutput + "\"";
-        assertTrue(realMessage, realOutput.indexOf(substring) >= 0);
+        assertTrue(realMessage, realOutput.contains(substring));
     }
 
     /**
@@ -173,7 +173,7 @@
         String realOutput = getOutput();
         String realMessage = (message != null) ? message : "expecting output to not contain \"" + substring
                 + "\" output was \"" + realOutput + "\"";
-        assertFalse(realMessage, realOutput.indexOf(substring) >= 0);
+        assertFalse(realMessage, realOutput.contains(substring));
     }
 
     /**
@@ -217,7 +217,7 @@
     public void assertDebuglogContaining(String substring) {
         String realLog = getFullLog();
         assertTrue("expecting debug log to contain \"" + substring + "\" log was \"" + realLog + "\"",
-                realLog.indexOf(substring) >= 0);
+                realLog.contains(substring));
     }
 
     /**
@@ -501,7 +501,7 @@
             executeTarget(target);
         } catch (org.apache.tools.ant.BuildException ex) {
             buildException = ex;
-            if ((null != contains) && (ex.getMessage().indexOf(contains) == -1)) {
+            if ((null != contains) && (!ex.getMessage().contains(contains))) {
                 fail("Should throw BuildException because '" + cause + "' with message containing '" + contains
                         + "' (actual message '" + ex.getMessage() + "' instead)");
             }