diff --git a/solution/0700-0799/0747.Largest Number At Least Twice of Others/README.md b/solution/0700-0799/0747.Largest Number At Least Twice of Others/README.md
index c4a40115b42da..335c387ef59a2 100644
--- a/solution/0700-0799/0747.Largest Number At Least Twice of Others/README.md	
+++ b/solution/0700-0799/0747.Largest Number At Least Twice of Others/README.md	
@@ -58,7 +58,20 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
-
+class Solution {
+  public int dominantIndex(int[] nums) {
+    int maxIndex = 0;
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] > nums[maxIndex])
+        maxIndex = i;
+    }
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] * 2 > nums[maxIndex] && i != maxIndex)
+        return -1;
+    }
+    return maxIndex;
+  }
+}
 ```
 
 ### **...**
diff --git a/solution/0700-0799/0747.Largest Number At Least Twice of Others/README_EN.md b/solution/0700-0799/0747.Largest Number At Least Twice of Others/README_EN.md
index b442a5b5abd08..81c1fa595dcde 100644
--- a/solution/0700-0799/0747.Largest Number At Least Twice of Others/README_EN.md	
+++ b/solution/0700-0799/0747.Largest Number At Least Twice of Others/README_EN.md	
@@ -50,7 +50,20 @@ The index of value 6 is 1, so we return 1.
 ### **Java**
 
 ```java
-
+class Solution {
+  public int dominantIndex(int[] nums) {
+    int maxIndex = 0;
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] > nums[maxIndex])
+        maxIndex = i;
+    }
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] * 2 > nums[maxIndex] && i != maxIndex)
+        return -1;
+    }
+    return maxIndex;
+  }
+}
 ```
 
 ### **...**
diff --git a/solution/0700-0799/0747.Largest Number At Least Twice of Others/Solution.java b/solution/0700-0799/0747.Largest Number At Least Twice of Others/Solution.java
new file mode 100644
index 0000000000000..3561eee8bd96b
--- /dev/null
+++ b/solution/0700-0799/0747.Largest Number At Least Twice of Others/Solution.java	
@@ -0,0 +1,14 @@
+class Solution {
+  public int dominantIndex(int[] nums) {
+    int maxIndex = 0;
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] > nums[maxIndex])
+        maxIndex = i;
+    }
+    for (int i = 0; i < nums.length; i++) {
+      if (nums[i] * 2 > nums[maxIndex] && i != maxIndex)
+        return -1;
+    }
+    return maxIndex;
+  }
+}
\ No newline at end of file