diff --git a/problems/0078.子集.md b/problems/0078.子集.md
index 8c68843d..77854133 100644
--- a/problems/0078.子集.md
+++ b/problems/0078.子集.md
@@ -177,7 +177,33 @@ public:
 
 
 Java：
+```java
+class Solution {
+    List<List<Integer>> result = new ArrayList<>();// 存放符合条件结果的集合
+    LinkedList<Integer> path = new LinkedList<>();// 用来存放符合条件结果
+    public List<List<Integer>> subsets(int[] nums) {
+        if (nums.length == 0){
+            result.add(new ArrayList<>());
+            return result;
+        }
+        Arrays.sort(nums);
+        subsetsHelper(nums, 0);
+        return result;
+    }
 
+    private void subsetsHelper(int[] nums, int startIndex){
+        result.add(new ArrayList<>(path));//「遍历这个树的时候，把所有节点都记录下来，就是要求的子集集合」。
+        if (startIndex >= nums.length){ //终止条件可不加
+            return;
+        }
+        for (int i = startIndex; i < nums.length; i++){
+            path.add(nums[i]);
+            subsetsHelper(nums, i + 1);
+            path.removeLast();
+        }
+    }
+}
+```
 
 Python：