If you have changed the metadata for an Adapter, you can use the "Sync Adapters" feature in iStudio to push new metadata to selected Adapters and restart them (in version 9.0.4, this menu item was called "Push Metadata"):
  1. Select File from the main menu, and then Sync Adapters / Push Metadata
  2. Select the Adapters you want to synchronize (HINT: Press Ctrl while clicking to select individual Adapters, or press Shift while clicking to select a range)
  3. Click OK

To simply restart an Adapter, without using iStudio, you can use these methods:

If you are using 9.0.4 or 10.1.2.0.0, or the Adapter was created using the copyAdapter script:

  1. Run the stop.bat script in the Adapter folder
  2. Remove the persistence subfolder in the Adapter folder (optional)
  3. Run the start.bat script in the Adapter folder

If you are using 10.1.2.0.2, and the Adapter is monitored by OPMN, you can use command line tools (see below) or Application Server Control:

  1. Go to Application Server Control for your Middle-Tier
  2. Click on InterConnect
  3. Check the Adapter(s) you want to restart
  4. Click the Restart button
  5. When asked if you want to proceed, click Yes
This is how you can restart an Adapter using the command line: 
cd /d D:\ora101202mt\opmn\bin
opmnctl restartproc ias-component="InterConnect" process-type="AQApp"