diff --git a/src/main/java/xyz/zhouxy/plusone/commons/util/BigDecimals.java b/src/main/java/xyz/zhouxy/plusone/commons/util/BigDecimals.java
index 3b6bf78..f56a998 100644
--- a/src/main/java/xyz/zhouxy/plusone/commons/util/BigDecimals.java
+++ b/src/main/java/xyz/zhouxy/plusone/commons/util/BigDecimals.java
@@ -6,7 +6,6 @@ import javax.annotation.Nullable;
 
 import org.apache.commons.lang3.StringUtils;
 
-import com.google.common.annotations.Beta;
 import com.google.common.base.Preconditions;
 
 public class BigDecimals {
@@ -17,21 +16,26 @@ public class BigDecimals {
         return (a == b) || (a != null && a.compareTo(b) == 0);
     }
 
-    @Beta
-    public static boolean greaterThan(BigDecimal a, BigDecimal b) {
+    public static boolean gt(BigDecimal a, BigDecimal b) {
         Preconditions.checkNotNull(a, "Parameter could not be null.");
         Preconditions.checkNotNull(b, "Parameter could not be null.");
         return (a != b) && (a.compareTo(b) > 0);
     }
 
-    @Beta
-    public static boolean lessThan(BigDecimal a, BigDecimal b) {
+    public static boolean ge(BigDecimal a, BigDecimal b) {
+        return gt(a, b) || equals(a, b);
+    }
+
+    public static boolean lt(BigDecimal a, BigDecimal b) {
         Preconditions.checkNotNull(a, "Parameter could not be null.");
         Preconditions.checkNotNull(b, "Parameter could not be null.");
         return (a != b) && (a.compareTo(b) < 0);
     }
 
-    @Beta
+    public static boolean le(BigDecimal a, BigDecimal b) {
+        return lt(a, b) || equals(a, b);
+    }
+
     public static BigDecimal of(final String val) {
         return (StringUtils.isBlank(val)) ? ZERO : new BigDecimal(val);
     }
diff --git a/src/main/java/xyz/zhouxy/plusone/commons/util/Enumeration.java b/src/main/java/xyz/zhouxy/plusone/commons/util/Enumeration.java
index 0d0a8a2..2f1b18a 100644
--- a/src/main/java/xyz/zhouxy/plusone/commons/util/Enumeration.java
+++ b/src/main/java/xyz/zhouxy/plusone/commons/util/Enumeration.java
@@ -85,9 +85,8 @@ public abstract class Enumeration<T extends Enumeration<T>> implements Comparabl
             this.valueMap = valueMap;
         }
 
-        @SafeVarargs
         @StaticFactoryMethod(ValueSet.class)
-        public static <T extends Enumeration<T>> ValueSet<T> of(T... values) {
+        public static <T extends Enumeration<T>> ValueSet<T> of(T[] values) {
             Map<Integer, T> temp = Arrays.stream(values)
                     .collect(Collectors.toMap(Enumeration::getId, Function.identity()));
             return new ValueSet<>(Collections.unmodifiableMap(temp));
diff --git a/src/main/java/xyz/zhouxy/plusone/commons/util/Numbers.java b/src/main/java/xyz/zhouxy/plusone/commons/util/Numbers.java
index 4cbd3c0..3c499f0 100644
--- a/src/main/java/xyz/zhouxy/plusone/commons/util/Numbers.java
+++ b/src/main/java/xyz/zhouxy/plusone/commons/util/Numbers.java
@@ -16,6 +16,8 @@
 
 package xyz.zhouxy.plusone.commons.util;
 
+import java.math.BigDecimal;
+
 /**
  * Numbers
  *
@@ -23,10 +25,6 @@ package xyz.zhouxy.plusone.commons.util;
  */
 public class Numbers {
 
-    private Numbers() {
-        throw new IllegalStateException("Utility class");
-    }
-
     // sum
 
     public static int sum(final short... numbers) {
@@ -69,6 +67,14 @@ public class Numbers {
         return result;
     }
 
+    public static BigDecimal sum(final BigDecimal... numbers) {
+        BigDecimal result = BigDecimals.of("0.00");
+        for (BigDecimal number : numbers) {
+            result = result.add(number);
+        }
+        return result;
+    }
+
     // between
 
     public static boolean between(short value, short min, short max) {
@@ -90,4 +96,12 @@ public class Numbers {
     public static boolean between(double value, double min, double max) {
         return value >= min && value < max;
     }
+
+    public static boolean between(BigDecimal value, BigDecimal min, BigDecimal max) {
+        return BigDecimals.ge(value, min) && BigDecimals.lt(value, max);
+    }
+
+    private Numbers() {
+        throw new IllegalStateException("Utility class");
+    }
 }
diff --git a/src/test/java/xyz/zhouxy/plusone/commons/EnumerationTests.java b/src/test/java/xyz/zhouxy/plusone/commons/EnumerationTests.java
index dd04458..6bc4506 100644
--- a/src/test/java/xyz/zhouxy/plusone/commons/EnumerationTests.java
+++ b/src/test/java/xyz/zhouxy/plusone/commons/EnumerationTests.java
@@ -38,7 +38,7 @@ final class EntityStatus extends Enumeration<EntityStatus> {
     public static final EntityStatus AVAILABLE = new EntityStatus(0, "正常");
     public static final EntityStatus DISABLED = new EntityStatus(1, "禁用");
 
-    private static final ValueSet<EntityStatus> VALUE_SET = ValueSet.of(AVAILABLE, DISABLED);
+    private static final ValueSet<EntityStatus> VALUE_SET = ValueSet.of(new EntityStatus[] { AVAILABLE, DISABLED });
 
     public static EntityStatus of(int value) {
         return VALUE_SET.get(value);
@@ -57,7 +57,7 @@ final class Result extends Enumeration<Result> {
     public static final Result SUCCESSFUL = new Result(1, "成功");
     public static final Result FAILURE = new Result(0, "失败");
 
-    private static final ValueSet<Result> VALUE_SET = ValueSet.of(SUCCESSFUL, FAILURE);
+    private static final ValueSet<Result> VALUE_SET = ValueSet.of(new Result[] { SUCCESSFUL, FAILURE });
 
     public static Result of(int id) {
         return VALUE_SET.get(id);