使用 StringUtils 的 leftPad 和 rightPad 即可。

src/main/java/xyz/zhouxy/plusone/commons/util/StrUtil.java

@@ -1,34 +0,0 @@
-package xyz.zhouxy.plusone.commons.util;
-
-import java.util.Arrays;
-
-public class StrUtil {
-
-    public static String fillBefore(String src, int minLength, char c) {
-        if (src.length() >= minLength) {
-            return src;
-        }
-        char[] result = new char[minLength];
-        Arrays.fill(result, 0, minLength - src.length(), c);
-        for (int i = 1; i <= src.length(); i++) {
-            result[minLength - i] = src.charAt(src.length() - i);
-        }
-        return String.valueOf(result);
-    }
-
-    public static String fillAfter(String src, int minLength, char c) {
-        if (src.length() >= minLength) {
-            return src;
-        }
-        char[] result = new char[minLength];
-        for (int i = 0; i < src.length(); i++) {
-            result[i] = src.charAt(i);
-        }
-        Arrays.fill(result, src.length(), result.length, c);
-        return String.valueOf(result);
-    }
-
-    private StrUtil() {
-        throw new IllegalStateException("Utility class");
-    }
-}