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copied!<p>You can call the method using reflection and fail gracefully in case of errors (like missing class or methods). See <a href="http://download.oracle.com/javase/6/docs/api/java/lang/reflect/package-summary.html" rel="noreferrer">java.lang.reflect</a></p> <p>Other option is to compile code in level 9 but surround with try/catch to catch errors that would arise from execution on lower level. It could be fairly error prone, though, and I'd think twice about doing it.</p> <hr> <p>Update</p> <p>Here is test code</p> <pre><code>public void onCreate(Bundle savedInstanceState) { try { // First we try reflection approach. // Expected result // in 2.3 we print some value in log but no exception // in 2.2 we print NoSuchMethodException // In both levels we get our screen displayed after catch Method m = SensorManager.class.getMethod("getAltitude",Float.TYPE, Float.TYPE); Float a = (Float)m.invoke(null, 0.0f, 0.0f); Log.w("test","Result 1: " + a); } catch (Throwable e) { Log.e("test", "error 1",e); } try { // Now we try compiling against 2.3 // Expected result // in 2.3 we print some value in log but no exception // in 2.2 we print NoSuchMethodError (Note that it is an error not exception but it's still caught) // In both levels we get our screen displayed after catch float b = SensorManager.getAltitude(0.0f, 0.0f); Log.w("test","Result 2: " + b); } catch (Throwable e) { Log.e("test", "error 2",e); } super.onCreate(savedInstanceState); setContentView(R.layout.main); } </code></pre> <p>Results:</p> <p>2.3</p> <pre><code>09-14 07:04:50.374: DEBUG/dalvikvm(589): Debugger has detached; object registry had 1 entries 09-14 07:04:50.924: WARN/test(597): Result 1: NaN 09-14 07:04:51.014: WARN/test(597): Result 2: NaN 09-14 07:04:51.384: INFO/ActivityManager(75): Displayed com.example/.MyActivity: +1s65ms </code></pre> <p>2.2</p> <pre><code>09-14 07:05:48.220: INFO/dalvikvm(382): Could not find method android.hardware.SensorManager.getAltitude, referenced from method com.example.MyActivity.onCreate 09-14 07:05:48.220: WARN/dalvikvm(382): VFY: unable to resolve static method 2: Landroid/hardware/SensorManager;.getAltitude (FF)F 09-14 07:05:48.220: DEBUG/dalvikvm(382): VFY: replacing opcode 0x71 at 0x0049 09-14 07:05:48.220: DEBUG/dalvikvm(382): VFY: dead code 0x004c-0064 in Lcom/example/MyActivity;.onCreate (Landroid/os/Bundle;)V 09-14 07:05:48.300: ERROR/test(382): error 1 java.lang.NoSuchMethodException: getAltitude at java.lang.ClassCache.findMethodByName(ClassCache.java:308) </code></pre> <p>Skipped stack trace</p> <pre><code>09-14 07:05:48.300: ERROR/test(382): error 2 java.lang.NoSuchMethodError: android.hardware.SensorManager.getAltitude at com.example.MyActivity.onCreate(MyActivity.java:35) </code></pre> <p>Skipped more stack trace</p> <pre><code>09-14 07:05:48.330: DEBUG/dalvikvm(33): GC_EXPLICIT freed 2 objects / 64 bytes in 180ms 09-14 07:05:48.520: INFO/ActivityManager(59): Displayed activity com.example/.MyActivity: 740 ms (total 740 ms) </code></pre>

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