探究编译后，try-with-resources括号中的object是否关闭，以及两种写法编译后的对比

源码（@TargetApi(Build.VERSION_CODES.KITKAT)）

public List<T> test1() {

        String sql = "selxe xxxxxxxxxxx";

        try (Cursor cursor = dbManager.getReadableDatabase().rawQuery(sql, null)) {

            List<T> lst = new ArrayList<>();

            while (cursor.moveToNext()) {

                lst.add(findEntity(cursor));

            }

            return lst;

        }

    }

    public List<T> test2() {

        String sql = "selxe xxxxxxxxxxx";

        Cursor cursor = dbManager.getReadableDatabase().rawQuery(sql, null);

        try {

            List<T> lst = new ArrayList<>();

            while (cursor.moveToNext()) {

                lst.add(findEntity(cursor));

            }

            return lst;

        } finally {

            cursor.close();

        }

    }

反编译后

public List<T> test1()

  {

    Cursor localCursor = this.dbManager.getReadableDatabase().rawQuery("selxe xxxxxxxxxxx", null);

    try

    {

      localArrayList = new ArrayList();

      while (localCursor.moveToNext())

        localArrayList.add(findEntity(localCursor));

    }

    catch (Throwable localThrowable3)

    {

      ArrayList localArrayList;

      Object localObject1;

      try

      {

        throw localThrowable3;

      }

      finally

      {

        localThrowable1 = localThrowable3;

      }

      if ((localCursor == null) || (localThrowable1 != null));

      while (true)

      {

        try

        {

          localCursor.close();

          throw localObject1;

          if ((localCursor == null) || (0 != 0))

            try

            {

              localCursor.close();

              return localArrayList;

            }

            catch (Throwable localThrowable4)

            {

              null.addSuppressed(localThrowable4);

              return localArrayList;

            }

          localCursor.close();

          return localArrayList;

        }

        catch (Throwable localThrowable2)

        {

          localThrowable1.addSuppressed(localThrowable2);

          continue;

        }

        localCursor.close();

      }

    }

    finally

    {

      while (true)

        Throwable localThrowable1 = null;

    }

  }

  public List<T> test2()

  {

    Cursor localCursor = this.dbManager.getReadableDatabase().rawQuery("selxe xxxxxxxxxxx", null);

    ArrayList localArrayList;

    try

    {

      localArrayList = new ArrayList();

      while (localCursor.moveToNext())

        localArrayList.add(findEntity(localCursor));

    }

    finally

    {

      localCursor.close();

    }

    localCursor.close();

    return localArrayList;

  }

The try-with-resources statement is a try statement that declares one or more resources. A resource is an object that must be closed after the program is finished with it. The try-with-resources statement ensures that each resource is closed at the end of the statement. Any object that implements java.lang.AutoCloseable, which includes all objects which implement java.io.Closeable, can be used as a resource.

参考：https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html

巴特西

探究编译后，try-with-resources括号中的object是否关闭，以及两种写法编译后的对比

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