diff --git a/src/main/java/org/apache/groovy/parser/antlr4/util/StringUtils.java b/src/main/java/org/apache/groovy/parser/antlr4/util/StringUtils.java
index d4fc339e1c1..a312eeed7b4 100644
--- a/src/main/java/org/apache/groovy/parser/antlr4/util/StringUtils.java
+++ b/src/main/java/org/apache/groovy/parser/antlr4/util/StringUtils.java
@@ -20,143 +20,57 @@
 
 import groovy.lang.Closure;
 import org.apache.groovy.util.Maps;
-import org.codehaus.groovy.runtime.StringGroovyMethods;
 
 import java.util.Map;
 import java.util.regex.Pattern;
 
+import static org.codehaus.groovy.runtime.StringGroovyMethods.replaceAll;
+
 /**
  * Utilities for handling strings
  *
  */
 public class StringUtils {
-	private static final String BACKSLASH = "\\";
-	private static final Pattern HEX_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\u([0-9abcdefABCDEF]{4})");
-	private static final Pattern OCTAL_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\([0-3]?[0-7]?[0-7])");
-	private static final Pattern STANDARD_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\([btnfrs\"'])");
-	private static final Pattern LINE_ESCAPE_PATTERN = Pattern.compile("(\\\\*)\\\\\r?\n");
-
-	public static String replaceHexEscapes(String text) {
-		if (!text.contains(BACKSLASH)) {
-			return text;
-		}
-
-		return StringGroovyMethods.replaceAll((CharSequence) text, HEX_ESCAPES_PATTERN, new Closure<Void>(null, null) {
-			Object doCall(String _0, String _1, String _2) {
-				if (isLengthOdd(_1)) {
-					return _0;
-				}
-
-				return _1 + new String(Character.toChars(Integer.parseInt(_2, 16)));
-			}
-		});
+    public static final int NONE_SLASHY = 0;
+    public static final int SLASHY = 1;
+    public static final int DOLLAR_SLASHY = 2;
+
+    public static String replaceEscapes(String text, int slashyType) {
+        if (slashyType == SLASHY || slashyType == DOLLAR_SLASHY) {
+            text = StringUtils.replaceHexEscapes(text);
+            text = StringUtils.replaceLineEscape(text);
+
+            if (slashyType == SLASHY) {
+                text = replace(text,"\\/", "/");
+            } else if (slashyType == DOLLAR_SLASHY) {
+                text = replace(text,"$/", "/");
+                text = replace(text,"$$", "$");
+            }
+        } else if (slashyType == NONE_SLASHY) {
+            text = StringUtils.replaceEscapes(text);
+        } else {
+            throw new IllegalArgumentException("Invalid slashyType: " + slashyType);
+        }
+
+        return text;
+    }
+
+    public static String replaceHexEscapes(String text) {
+		if (!text.contains(BACKSLASH)) return text;
+		return replaceAll((CharSequence) text, HEX_ESCAPES_PATTERN, REPLACE_HEX_ESCAPES);
 	}
 
 	public static String replaceOctalEscapes(String text) {
-		if (!text.contains(BACKSLASH)) {
-			return text;
-		}
-
-		return StringGroovyMethods.replaceAll((CharSequence) text, OCTAL_ESCAPES_PATTERN, new Closure<Void>(null, null) {
-			Object doCall(String _0, String _1, String _2) {
-				if (isLengthOdd(_1)) {
-					return _0;
-				}
-
-				return _1 + new String(Character.toChars(Integer.parseInt(_2, 8)));
-			}
-		});
+		if (!text.contains(BACKSLASH)) return text;
+		return replaceAll((CharSequence) text, OCTAL_ESCAPES_PATTERN, REPLACE_OCTAL_ESCAPES);
 	}
 
-	private static final Map<Character, Character> STANDARD_ESCAPES = Maps.of(
-			'b', '\b',
-			't', '\t',
-			'n', '\n',
-			'f', '\f',
-			'r', '\r',
-			's', ' '
-	);
-
-	public static String replaceStandardEscapes(String text) {
-		if (!text.contains(BACKSLASH)) {
-			return text;
-		}
-
-		String result = StringGroovyMethods.replaceAll((CharSequence) text, STANDARD_ESCAPES_PATTERN, new Closure<Void>(null, null) {
-			Object doCall(String _0, String _1, String _2) {
-				if (isLengthOdd(_1)) {
-					return _0;
-				}
-
-				Character character = STANDARD_ESCAPES.get(_2.charAt(0));
-				return _1 + (character != null ? character : _2);
-			}
-		});
-
+    public static String replaceStandardEscapes(String text) {
+		if (!text.contains(BACKSLASH)) return text;
+		final String result = replaceAll((CharSequence) text, STANDARD_ESCAPES_PATTERN, REPLACE_STANDARD_ESCAPES);
 		return replace(result,"\\\\", "\\");
 	}
 
-	public static final int NONE_SLASHY = 0;
-	public static final int SLASHY = 1;
-	public static final int DOLLAR_SLASHY = 2;
-
-	public static String replaceEscapes(String text, int slashyType) {
-		if (slashyType == SLASHY || slashyType == DOLLAR_SLASHY) {
-			text = StringUtils.replaceHexEscapes(text);
-			text = StringUtils.replaceLineEscape(text);
-
-			if (slashyType == SLASHY) {
-				text = replace(text,"\\/", "/");
-			}
-
-			if (slashyType == DOLLAR_SLASHY) {
-				text = replace(text,"$/", "/");
-				text = replace(text,"$$", "$");
-			}
-
-		} else if (slashyType == NONE_SLASHY) {
-			text = StringUtils.replaceEscapes(text);
-		} else {
-			throw new IllegalArgumentException("Invalid slashyType: " + slashyType);
-		}
-
-		return text;
-	}
-
-	private static String replaceEscapes(String text) {
-		if (!text.contains(BACKSLASH)) {
-			return text;
-		}
-
-		text = replace(text,"\\$", "$");
-
-		text = StringUtils.replaceLineEscape(text);
-
-		return StringUtils.replaceStandardEscapes(replaceHexEscapes(replaceOctalEscapes(text)));
-	}
-
-	private static String replaceLineEscape(String text) {
-		if (!text.contains(BACKSLASH)) {
-			return text;
-		}
-
-		text = StringGroovyMethods.replaceAll((CharSequence) text, LINE_ESCAPE_PATTERN, new Closure<Void>(null, null) {
-			Object doCall(String _0, String _1) {
-				if (isLengthOdd(_1)) {
-					return _0;
-				}
-
-				return _1;
-			}
-		});
-
-		return text;
-	}
-
-	private static boolean isLengthOdd(String str) {
-		return null != str && str.length() % 2 == 1;
-	}
-
 	public static String removeCR(String text) {
 		return replace(text,"\r\n", "\n");
 	}
@@ -167,7 +81,6 @@ public static long countChar(String text, char c) {
 
 	public static String trimQuotations(String text, int quotationLength) {
 		int length = text.length();
-
 		return length == quotationLength << 1 ? "" : text.substring(quotationLength, length - quotationLength);
 	}
 
@@ -200,9 +113,8 @@ public static boolean matches(String text, Pattern pattern) {
 	 *  {@code null} if null String input
 	 */
 	public static String replace(final String text, String searchString, final String replacement) {
-		if (isEmpty(text) || isEmpty(searchString) || replacement == null) {
-			return text;
-		}
+		if (isEmpty(text) || isEmpty(searchString) || replacement == null) return text;
+
 		int start = 0;
 		int end = text.indexOf(searchString, start);
 		if (end == INDEX_NOT_FOUND) {
@@ -245,10 +157,65 @@ public static boolean isEmpty(final CharSequence cs) {
 		return cs == null || cs.length() == 0;
 	}
 
-	/**
+    private static String replaceEscapes(String text) {
+        if (!text.contains(BACKSLASH)) return text;
+        text = replace(text,"\\$", "$");
+        text = StringUtils.replaceLineEscape(text);
+        return StringUtils.replaceStandardEscapes(replaceHexEscapes(replaceOctalEscapes(text)));
+    }
+
+    private static String replaceLineEscape(String text) {
+        if (!text.contains(BACKSLASH)) return text;
+        text = replaceAll((CharSequence) text, LINE_ESCAPE_PATTERN, REPLACE_LINE_ESCAPE);
+        return text;
+    }
+
+    private static boolean isLengthOdd(String str) {
+        return null != str && str.length() % 2 == 1;
+    }
+
+    /**
 	 * Copied from Apache commons-lang3-3.6
 	 *
 	 * Represents a failed index search.
 	 */
 	private static final int INDEX_NOT_FOUND = -1;
-}
\ No newline at end of file
+    private static final String BACKSLASH = "\\";
+    private static final Pattern HEX_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\u([0-9abcdefABCDEF]{4})");
+    private static final Pattern OCTAL_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\([0-3]?[0-7]?[0-7])");
+    private static final Pattern STANDARD_ESCAPES_PATTERN = Pattern.compile("(\\\\*)\\\\([btnfrs\"'])");
+    private static final Pattern LINE_ESCAPE_PATTERN = Pattern.compile("(\\\\*)\\\\\r?\n");
+    private static final Map<Character, Character> STANDARD_ESCAPES = Maps.of(
+        'b', '\b',
+        't', '\t',
+        'n', '\n',
+        'f', '\f',
+        'r', '\r',
+        's', ' '
+    );
+    private static final Closure<String> REPLACE_STANDARD_ESCAPES = new Closure<String>(null, null) {
+        String doCall(String _0, String _1, String _2) {
+            if (isLengthOdd(_1)) return _0;
+            final Character character = STANDARD_ESCAPES.get(_2.charAt(0));
+            return _1 + (character != null ? character : _2);
+        }
+    };
+    private static final Closure<String> REPLACE_OCTAL_ESCAPES = new Closure<String>(null, null) {
+        String doCall(String _0, String _1, String _2) {
+            if (isLengthOdd(_1)) return _0;
+            return _1 + new String(Character.toChars(Integer.parseInt(_2, 8)));
+        }
+    };
+    private static final Closure<String> REPLACE_HEX_ESCAPES = new Closure<String>(null, null) {
+        String doCall(String _0, String _1, String _2) {
+            if (isLengthOdd(_1)) return _0;
+            return _1 + new String(Character.toChars(Integer.parseInt(_2, 16)));
+        }
+    };
+    private static final Closure<String> REPLACE_LINE_ESCAPE = new Closure<String>(null, null) {
+        String doCall(String _0, String _1) {
+            if (isLengthOdd(_1)) return _0;
+            return _1;
+        }
+    };
+}