[hotfix] Clean up StringUtils and remove unused methods.

flink-connectors/flink-connector-kafka-0.8/src/main/java/org/apache/flink/streaming/connectors/kafka/internals/SimpleConsumerThread.java

@@ -30,7 +30,7 @@ import kafka.javaapi.message.ByteBufferMessageSet;
 import kafka.message.MessageAndOffset;
 
 import org.apache.flink.streaming.util.serialization.KeyedDeserializationSchema;
-import org.apache.flink.util.StringUtils;
+import org.apache.flink.util.ExceptionUtils;
 
 import org.apache.kafka.common.Node;
 
@@ -295,7 +295,7 @@ class SimpleConsumerThread<T> extends Thread {
 						}
 						else if (code != ErrorMapping.NoError()) {
 							exception += "\nException for " + fp.getTopic() +":"+ fp.getPartition() + ": " +
-									StringUtils.stringifyException(ErrorMapping.exceptionFor(code));
+									ExceptionUtils.stringifyException(ErrorMapping.exceptionFor(code));
 						}
 					}
 					if (partitionsToGetOffsetsFor.size() > 0) {
@@ -502,7 +502,7 @@ class SimpleConsumerThread<T> extends Thread {
 					if ((code = response.errorCode(part.getTopic(), part.getPartition())) != ErrorMapping.NoError()) {
 						exception.append("\nException for topic=").append(part.getTopic())
 							.append(" partition=").append(part.getPartition()).append(": ")
-							.append(StringUtils.stringifyException(ErrorMapping.exceptionFor(code)));
+							.append(ExceptionUtils.stringifyException(ErrorMapping.exceptionFor(code)));
 					}
 				}
 				if (++retries >= 3) {

flink-core/src/main/java/org/apache/flink/util/StringUtils.java

@@ -38,21 +38,7 @@ import static org.apache.flink.util.Preconditions.checkNotNull;
 @PublicEvolving
 public final class StringUtils {
 
-	/**
-	 * Empty private constructor to overwrite public one.
-	 */
-	private StringUtils() {}
-
-	/**
-	 * Makes a string representation of the exception.
-	 * 
-	 * @param e
-	 *        the exception to stringify
-	 * @return A string with exception name and call stack.
-	 */
-	public static String stringifyException(final Throwable e) {
-		return ExceptionUtils.stringifyException(e);
-	}
+	private static final char[] HEX_CHARS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
 
 	/**
 	 * Given an array of bytes it will convert the bytes to a hex string
@@ -65,15 +51,13 @@ public final class StringUtils {
 	 * @param end
 	 *        end index, exclusively
 	 * @return hex string representation of the byte array
-	 *
-	 * @see org.apache.commons.codec.binary.Hex#encodeHexString(byte[])
 	 */
 	public static String byteToHexString(final byte[] bytes, final int start, final int end) {
 		if (bytes == null) {
 			throw new IllegalArgumentException("bytes == null");
 		}
 		
-		final char[] HEX_CHARS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
+		
 
 		int length = end - start;
 		char[] out = new char[length * 2];
@@ -114,50 +98,6 @@ public final class StringUtils {
 		}
 		return bts;
 	}
-	
-	/**
-	 * Helper function to escape Strings for display in HTML pages. The function replaces
-	 * certain characters by their HTML coded correspondent.
-	 * 
-	 * @param str The string to escape.
-	 * @return The escaped string.
-	 */
-	public static String escapeHtml(String str) {
-		int len = str.length();
-		char[] s = str.toCharArray();
-		StringBuilder sb = new StringBuilder();
-
-		for (int i = 0; i < len; i += 1) {
-			char c = s[i];
-			if ((c == '\\') || (c == '"') || (c == '/')) {
-				sb.append('\\');
-				sb.append(c);
-			}
-			else if (c == '\b') {
-				sb.append("\\b");
-			} else if (c == '\t') {
-				sb.append("\\t");
-			} else if (c == '\n') {
-				sb.append("<br>");
-			} else if (c == '\f') {
-				sb.append("\\f");
-			} else if (c == '\r') {
-				sb.append("\\r");
-			} else if (c == '>') {
-				sb.append("&gt;");
-			} else if (c == '<') {
-				sb.append("&lt;");
-			} else if (c == '&') {
-				sb.append("&amp;");
-			} else if (c < ' ') {
-				// Unreadable throw away
-			} else {
-				sb.append(c);
-			}
-		}
-
-		return sb.toString();
-	}
 
 	/**
 	 * This method calls {@link Object#toString()} on the given object, unless the
@@ -310,7 +250,7 @@ public final class StringUtils {
 
 	/**
 	 * Writes a String to the given output.
-	 * The written string can be read with {@link #readNullableString(DataInputView)}.
+	 * The written string can be read with {@link #readString(DataInputView)}.
 	 *
 	 * @param str The string to write
 	 * @param out The output to write to
@@ -382,4 +322,9 @@ public final class StringUtils {
 		}
 		return true;
 	}
+
+	// ------------------------------------------------------------------------
+
+	/** Prevent instantiation of this utility class */
+	private StringUtils() {}
 }

flink-core/src/test/java/org/apache/flink/util/StringUtilsTest.java

@@ -40,13 +40,6 @@ public class StringUtilsTest extends TestLogger {
 		assertEquals("[1.0]", controlString);
 	}
 
-	@Test
-	public void testEscapeHTML() {
-		String testString = "\b \t / \n \f \r <default>";
-		String controlString = StringUtils.escapeHtml(testString);
-		assertEquals("\\b \\t \\/ <br> \\f \\r &lt;default&gt;", controlString);
-	}
-	
 	@Test
 	public void testStringToHexArray() {
 		String hex = "019f314a";