add taint normalize test cases

Author: lostsnow

dongtai-core/src/test/java/io/dongtai/iast/core/utils/StringUtilsTest.java

@@ -0,0 +1,28 @@
+package io.dongtai.iast.core.utils;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class StringUtilsTest {
+    @Test
+    public void normalize() {
+        int maxLength = 1024;
+        String str;
+        String nStr;
+        str = new String(new char[1000]).replace("\0", "a");
+        nStr = StringUtils.normalize(str, maxLength);
+        Assert.assertEquals("length", 1000, nStr.length());
+        str = new String(new char[10000]).replace("\0", "a");
+        nStr = StringUtils.normalize(str, maxLength);
+        Assert.assertEquals("length overflow", maxLength, nStr.length());
+
+        maxLength = 7;
+        str = new String(new char[10]).replace("\0", "a");
+        nStr = StringUtils.normalize(str, maxLength);
+        Assert.assertEquals("max len 7", "aa...aa", nStr);
+        maxLength = 6;
+        str = new String(new char[10]).replace("\0", "a");
+        nStr = StringUtils.normalize(str, maxLength);
+        Assert.assertEquals("max len 6", "aa...a", nStr);
+    }
+}