Repository: hbase Updated Branches: refs/heads/branch-1 c305b4436 -> ac6fd86d2
HBASE-13273 Make Result.EMPTY_RESULT read-only; currently it can be modified Signed-off-by: Sean Busbey <[email protected]> Conflicts: hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java Project: http://git-wip-us.apache.org/repos/asf/hbase/repo Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/ac6fd86d Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/ac6fd86d Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/ac6fd86d Branch: refs/heads/branch-1 Commit: ac6fd86d266e06696e31282de0844b897ef73864 Parents: c305b44 Author: Mikhail Antonov <[email protected]> Authored: Fri Mar 20 16:24:54 2015 -0700 Committer: Sean Busbey <[email protected]> Committed: Tue Mar 24 13:15:43 2015 -0700 ---------------------------------------------------------------------- .../org/apache/hadoop/hbase/client/Result.java | 35 ++++++++++++++++++-- .../apache/hadoop/hbase/client/TestResult.java | 27 +++++++++++++++ 2 files changed, 59 insertions(+), 3 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/hbase/blob/ac6fd86d/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java ---------------------------------------------------------------------- diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java index 66a63ca..10d5174 100644 --- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java +++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java @@ -100,7 +100,7 @@ public class Result implements CellScannable, CellScanner { private static ThreadLocal<byte[]> localBuffer = new ThreadLocal<byte[]>(); private static final int PAD_WIDTH = 128; - public static final Result EMPTY_RESULT = new Result(); + public static final Result EMPTY_RESULT = new Result(true); private final static int INITIAL_CELLSCANNER_INDEX = -1; @@ -110,6 +110,8 @@ public class Result implements CellScannable, CellScanner { private int cellScannerIndex = INITIAL_CELLSCANNER_INDEX; private ClientProtos.RegionLoadStats stats; + private final boolean readonly; + /** * Creates an empty Result w/ no KeyValue payload; returns null if you call {@link #rawCells()}. * Use this to represent no results if <code>null</code> won't do or in old 'mapred' as oppposed to 'mapreduce' package @@ -117,7 +119,16 @@ public class Result implements CellScannable, CellScanner { * instance with a {@link #copyFrom(Result)} call. */ public Result() { - super(); + this(false); + } + + /** + * Allows to construct special purpose immutable Result objects, + * such as EMPTY_RESULT. + * @param readonly whether this Result instance is readonly + */ + private Result(boolean readonly) { + this.readonly = readonly; } /** @@ -125,7 +136,7 @@ public class Result implements CellScannable, CellScanner { */ @Deprecated public Result(KeyValue [] cells) { - this.cells = cells; + this(cells, null, false, false); } /** @@ -187,6 +198,7 @@ public class Result implements CellScannable, CellScanner { this.exists = exists; this.stale = stale; this.partial = partial; + this.readonly = false; } /** @@ -909,9 +921,12 @@ public class Result implements CellScannable, CellScanner { /** * Copy another Result into this one. Needed for the old Mapred framework + * @throws UnsupportedOperationException if invoked on instance of EMPTY_RESULT + * (which is supposed to be immutable). * @param other */ public void copyFrom(Result other) { + checkReadonly(); this.row = null; this.familyMap = null; this.cells = other.cells; @@ -941,6 +956,7 @@ public class Result implements CellScannable, CellScanner { } public void setExists(Boolean exists) { + checkReadonly(); this.exists = exists; } @@ -966,8 +982,11 @@ public class Result implements CellScannable, CellScanner { /** * Add load information about the region to the information about the result * @param loadStats statistics about the current region from which this was returned + * @throws UnsupportedOperationException if invoked on instance of EMPTY_RESULT + * (which is supposed to be immutable). */ public void addResults(ClientProtos.RegionLoadStats loadStats) { + checkReadonly(); this.stats = loadStats; } @@ -978,4 +997,14 @@ public class Result implements CellScannable, CellScanner { public ClientProtos.RegionLoadStats getStats() { return stats; } + + /** + * All methods modifying state of Result object must call this method + * to ensure that special purpose immutable Results can't be accidentally modified. + */ + private void checkReadonly() { + if (readonly == true) { + throw new UnsupportedOperationException("Attempting to modify readonly EMPTY_RESULT!"); + } + } } http://git-wip-us.apache.org/repos/asf/hbase/blob/ac6fd86d/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java ---------------------------------------------------------------------- diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java index f631a20..d9496b3 100644 --- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java +++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestResult.java @@ -34,6 +34,7 @@ import org.apache.hadoop.hbase.Cell; import org.apache.hadoop.hbase.CellScanner; import org.apache.hadoop.hbase.CellUtil; import org.apache.hadoop.hbase.KeyValue; +import org.apache.hadoop.hbase.protobuf.generated.ClientProtos; import org.apache.hadoop.hbase.testclassification.SmallTests; import org.apache.hadoop.hbase.util.Bytes; import org.junit.experimental.categories.Category; @@ -228,6 +229,32 @@ public class TestResult extends TestCase { } } + /** + * Verifies that one can't modify instance of EMPTY_RESULT. + */ + public void testEmptyResultIsReadonly() { + Result emptyResult = Result.EMPTY_RESULT; + Result otherResult = new Result(); + + try { + emptyResult.copyFrom(otherResult); + fail("UnsupportedOperationException should have been thrown!"); + } catch (UnsupportedOperationException ex) { + LOG.debug("As expected: " + ex.getMessage()); + } + try { + emptyResult.addResults(ClientProtos.RegionLoadStats.getDefaultInstance()); + fail("UnsupportedOperationException should have been thrown!"); + } catch (UnsupportedOperationException ex) { + LOG.debug("As expected: " + ex.getMessage()); + } + try { + emptyResult.setExists(true); + fail("UnsupportedOperationException should have been thrown!"); + } catch (UnsupportedOperationException ex) { + LOG.debug("As expected: " + ex.getMessage()); + } + } /** * Microbenchmark that compares {@link Result#getValue} and {@link Result#loadValue} performance.
