Understanding the Execution Order of finally and return in Java

Interviewers often ask which executes first, finally or return, in Java. This article explains the execution order and the purpose of finally. finally is intended for cleanup actions that must run after try/catch, such as releasing database or Redis connections, and it is always executed before the method returns.

Example 1 shows a return inside try followed by a finally block without its own return. The output demonstrates that the return value is produced after the finally block runs.

package com.test;

/**
 * @author Damon
 * @date 2020年3月18日 上午11:02:08
 */
public class App {
  public static void main(String[] args) {
    System.out.println("return result: " + test());
  }

  public static int test() {
    try {
      Thread.sleep(1);
      System.out.println("執行 return 1");
      return 1; // return in try, finally runs afterwards
    } catch (InterruptedException e) {
      e.printStackTrace();
      return -1;
    } finally {
      System.out.println("执行 finally");
      //return 3;
    }
    //System.out.println("執行 return 2");
    //return 1;
  }
}

結果：
執行 return 1
执行 finally
return result: 1

Example 2 places a return 3 inside the finally block. In this case the finally return overrides the earlier return, and the method finally returns 3.

package com.test;

/**
 * @author Damon
 * @date 2020年3月18日 上午11:02:08
 */
public class App {
  public static void main(String[] args) {
    System.out.println("return result: " + test());
  }

  public static int test() {
    try {
      Thread.sleep(1);
      System.out.println("執行 return 1");
      return 1; // return in try, finally runs afterwards
    } catch (InterruptedException e) {
      e.printStackTrace();
      return -1;
    } finally {
      System.out.println("执行 finally");
      return 3;
    }
    //System.out.println("執行 return 2");
    //return 1;
  }
}

結果：
執行 return 1
执行 finally
return result: 3

Example 3 puts the return after the finally block. The finally still runs first, then the subsequent statements execute and the method returns the value from the later return.

package com.test;

/**
 * @author Damon
 * @date 2020年3月18日 上午11:02:08
 */
public class App {
  public static void main(String[] args) {
    System.out.println("return result: " + test());
  }

  public static int test() {
    try {
      Thread.sleep(1);
      //System.out.println("執行 return 1");
      //return 1;
    } catch (InterruptedException e) {
      e.printStackTrace();
      //return -1;
    } finally {
      System.out.println("执行 finally");
      //return 3;
    }
    System.out.println("執行 return 2");
    return 1;
  }
}

結果：
执行 finally
執行 return 2
return result: 1

The conclusions are: when a return appears before finally, the finally block runs first and then the return value is applied; if finally itself contains a return, that value is returned immediately, bypassing any previous return; and a return after finally is executed after the cleanup code.

The article also briefly distinguishes final, finally, and finalize: final declares immutable variables, non‑overridable methods, or non‑extendable classes; finally is a block that always executes in exception handling; finalize is a method of Object invoked by the garbage collector for resource cleanup.