Unconditionally use `Throwable.addSuppressed` in `Closer`.

It was [added in API Level 19](https://developer.android.com/reference/java/lang/Throwable#addSuppressed(java.lang.Throwable)), so we can rely on it.

We could do further work to migrate our own code (e.g., `ByteSource`) off `Closer` entirely. I'll leave that for the future.

RELNOTES=n/a
PiperOrigin-RevId: 631431407

8 files changed, 136 insertions, 522 deletions

diff --git a/android/guava-tests/test/com/google/common/io/ByteSourceTest.java b/android/guava-tests/test/com/google/common/io/ByteSourceTest.java
index 078b0f98b..3b63728df 100644
--- a/android/guava-tests/test/com/google/common/io/ByteSourceTest.java
+++ b/android/guava-tests/test/com/google/common/io/ByteSourceTest.java
@@ -23,6 +23,7 @@ import static com.google.common.io.TestOption.OPEN_THROWS;
 import static com.google.common.io.TestOption.READ_THROWS;
 import static com.google.common.io.TestOption.SKIP_THROWS;
 import static com.google.common.io.TestOption.WRITE_THROWS;
+import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertThrows;
 
@@ -31,9 +32,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.hash.Hashing;
-import com.google.common.io.Closer.LoggingSuppressor;
 import com.google.common.primitives.UnsignedBytes;
-import com.google.common.testing.TestLogHandler;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -378,61 +377,28 @@ public class ByteSourceTest extends IoTestCase {
       ImmutableSet.of(BROKEN_CLOSE_SINK, BROKEN_OPEN_SINK, BROKEN_WRITE_SINK);
 
   public void testCopyExceptions() {
-    if (Closer.create().suppressor instanceof LoggingSuppressor) {
-      // test that exceptions are logged
-
-      TestLogHandler logHandler = new TestLogHandler();
-      Closeables.logger.addHandler(logHandler);
-      try {
-        for (ByteSource in : BROKEN_SOURCES) {
-          runFailureTest(in, newNormalByteSink());
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(in, BROKEN_CLOSE_SINK);
-          assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, getAndResetRecords(logHandler));
-        }
-
-        for (ByteSink out : BROKEN_SINKS) {
-          runFailureTest(newNormalByteSource(), out);
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
+    // test that exceptions are suppressed
 
-          runFailureTest(BROKEN_CLOSE_SOURCE, out);
-          assertEquals(1, getAndResetRecords(logHandler));
-        }
+    for (ByteSource in : BROKEN_SOURCES) {
+      int suppressed = runSuppressionFailureTest(in, newNormalByteSink());
+      assertEquals(0, suppressed);
 
-        for (ByteSource in : BROKEN_SOURCES) {
-          for (ByteSink out : BROKEN_SINKS) {
-            runFailureTest(in, out);
-            assertTrue(getAndResetRecords(logHandler) <= 1);
-          }
-        }
-      } finally {
-        Closeables.logger.removeHandler(logHandler);
-      }
-    } else {
-      // test that exceptions are suppressed
+      suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
+      assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
+    }
 
-      for (ByteSource in : BROKEN_SOURCES) {
-        int suppressed = runSuppressionFailureTest(in, newNormalByteSink());
-        assertEquals(0, suppressed);
+    for (ByteSink out : BROKEN_SINKS) {
+      int suppressed = runSuppressionFailureTest(newNormalByteSource(), out);
+      assertEquals(0, suppressed);
 
-        suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
-        assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
-      }
+      suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
+      assertEquals(1, suppressed);
+    }
 
+    for (ByteSource in : BROKEN_SOURCES) {
       for (ByteSink out : BROKEN_SINKS) {
-        int suppressed = runSuppressionFailureTest(newNormalByteSource(), out);
-        assertEquals(0, suppressed);
-
-        suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
-        assertEquals(1, suppressed);
-      }
-
-      for (ByteSource in : BROKEN_SOURCES) {
-        for (ByteSink out : BROKEN_SINKS) {
-          int suppressed = runSuppressionFailureTest(in, out);
-          assertTrue(suppressed <= 1);
-        }
+        int suppressed = runSuppressionFailureTest(in, out);
+        assertThat(suppressed).isAtMost(1);
       }
     }
   }
@@ -441,20 +407,6 @@ public class ByteSourceTest extends IoTestCase {
     assertEquals(ByteSource.empty(), source.slice(0, 3).slice(4, 3));
   }
 
-  private static int getAndResetRecords(TestLogHandler logHandler) {
-    int records = logHandler.getStoredLogRecords().size();
-    logHandler.clear();
-    return records;
-  }
-
-  private static void runFailureTest(ByteSource in, ByteSink out) {
-    try {
-      in.copyTo(out);
-      fail();
-    } catch (IOException expected) {
-    }
-  }
-
   /**
    * @return the number of exceptions that were suppressed on the expected thrown exception
    */
@@ -463,7 +415,7 @@ public class ByteSourceTest extends IoTestCase {
       in.copyTo(out);
       fail();
     } catch (IOException expected) {
-      return CloserTest.getSuppressed(expected).length;
+      return expected.getSuppressed().length;
     }
     throw new AssertionError(); // can't happen
   }
diff --git a/android/guava-tests/test/com/google/common/io/CharSourceTest.java b/android/guava-tests/test/com/google/common/io/CharSourceTest.java
index a55ff4751..2eb9706da 100644
--- a/android/guava-tests/test/com/google/common/io/CharSourceTest.java
+++ b/android/guava-tests/test/com/google/common/io/CharSourceTest.java
@@ -20,14 +20,13 @@ import static com.google.common.io.TestOption.CLOSE_THROWS;
 import static com.google.common.io.TestOption.OPEN_THROWS;
 import static com.google.common.io.TestOption.READ_THROWS;
 import static com.google.common.io.TestOption.WRITE_THROWS;
+import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertThrows;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
-import com.google.common.io.Closer.LoggingSuppressor;
-import com.google.common.testing.TestLogHandler;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.Reader;
@@ -248,76 +247,29 @@ public class CharSourceTest extends IoTestCase {
       ImmutableSet.of(BROKEN_CLOSE_SINK, BROKEN_OPEN_SINK, BROKEN_WRITE_SINK);
 
   public void testCopyExceptions() {
-    if (Closer.create().suppressor instanceof LoggingSuppressor) {
-      // test that exceptions are logged
-
-      TestLogHandler logHandler = new TestLogHandler();
-      Closeables.logger.addHandler(logHandler);
-      try {
-        for (CharSource in : BROKEN_SOURCES) {
-          runFailureTest(in, newNormalCharSink());
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(in, BROKEN_CLOSE_SINK);
-          assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, getAndResetRecords(logHandler));
-        }
-
-        for (CharSink out : BROKEN_SINKS) {
-          runFailureTest(newNormalCharSource(), out);
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(BROKEN_CLOSE_SOURCE, out);
-          assertEquals(1, getAndResetRecords(logHandler));
-        }
-
-        for (CharSource in : BROKEN_SOURCES) {
-          for (CharSink out : BROKEN_SINKS) {
-            runFailureTest(in, out);
-            assertTrue(getAndResetRecords(logHandler) <= 1);
-          }
-        }
-      } finally {
-        Closeables.logger.removeHandler(logHandler);
-      }
-    } else {
-      // test that exceptions are suppressed
-
-      for (CharSource in : BROKEN_SOURCES) {
-        int suppressed = runSuppressionFailureTest(in, newNormalCharSink());
-        assertEquals(0, suppressed);
+    // test that exceptions are suppressed
 
-        suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
-        assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
-      }
+    for (CharSource in : BROKEN_SOURCES) {
+      int suppressed = runSuppressionFailureTest(in, newNormalCharSink());
+      assertEquals(0, suppressed);
 
-      for (CharSink out : BROKEN_SINKS) {
-        int suppressed = runSuppressionFailureTest(newNormalCharSource(), out);
-        assertEquals(0, suppressed);
+      suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
+      assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
+    }
 
-        suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
-        assertEquals(1, suppressed);
-      }
+    for (CharSink out : BROKEN_SINKS) {
+      int suppressed = runSuppressionFailureTest(newNormalCharSource(), out);
+      assertEquals(0, suppressed);
 
-      for (CharSource in : BROKEN_SOURCES) {
-        for (CharSink out : BROKEN_SINKS) {
-          int suppressed = runSuppressionFailureTest(in, out);
-          assertTrue(suppressed <= 1);
-        }
-      }
+      suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
+      assertEquals(1, suppressed);
     }
-  }
 
-  private static int getAndResetRecords(TestLogHandler logHandler) {
-    int records = logHandler.getStoredLogRecords().size();
-    logHandler.clear();
-    return records;
-  }
-
-  private static void runFailureTest(CharSource in, CharSink out) {
-    try {
-      in.copyTo(out);
-      fail();
-    } catch (IOException expected) {
+    for (CharSource in : BROKEN_SOURCES) {
+      for (CharSink out : BROKEN_SINKS) {
+        int suppressed = runSuppressionFailureTest(in, out);
+        assertThat(suppressed).isAtMost(1);
+      }
     }
   }
 
@@ -329,7 +281,7 @@ public class CharSourceTest extends IoTestCase {
       in.copyTo(out);
       fail();
     } catch (IOException expected) {
-      return CloserTest.getSuppressed(expected).length;
+      return expected.getSuppressed().length;
     }
     throw new AssertionError(); // can't happen
   }
diff --git a/android/guava-tests/test/com/google/common/io/CloserTest.java b/android/guava-tests/test/com/google/common/io/CloserTest.java
index 90c4eefe8..6dce40fda 100644
--- a/android/guava-tests/test/com/google/common/io/CloserTest.java
+++ b/android/guava-tests/test/com/google/common/io/CloserTest.java
@@ -25,13 +25,9 @@ import com.google.common.base.Objects;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Lists;
-import com.google.common.io.Closer.LoggingSuppressor;
-import com.google.common.testing.TestLogHandler;
 import java.io.Closeable;
 import java.io.IOException;
-import java.lang.reflect.Method;
 import java.util.List;
-import java.util.logging.LogRecord;
 import junit.framework.TestCase;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -49,11 +45,6 @@ public class CloserTest extends TestCase {
     suppressor = new TestSuppressor();
   }
 
-  @AndroidIncompatible // TODO(cpovirk): Look up Build.VERSION.SDK_INT reflectively.
-  public void testCreate() {
-    assertThat(Closer.create().suppressor).isInstanceOf(Closer.SuppressingSuppressor.class);
-  }
-
   public void testNoExceptionsThrown() throws IOException {
     Closer closer = new Closer(suppressor);
 
@@ -282,42 +273,8 @@ public class CloserTest extends TestCase {
         new Suppression(c1, c3Exception, c1Exception));
   }
 
-  public static void testLoggingSuppressor() throws IOException {
-    TestLogHandler logHandler = new TestLogHandler();
-
-    Closeables.logger.addHandler(logHandler);
-    try {
-      Closer closer = new Closer(new Closer.LoggingSuppressor());
-
-      TestCloseable c1 = closer.register(TestCloseable.throwsOnClose(new IOException()));
-      TestCloseable c2 = closer.register(TestCloseable.throwsOnClose(new RuntimeException()));
-      try {
-        throw closer.rethrow(new IOException("thrown"), IOException.class);
-      } catch (IOException expected) {
-      }
-
-      assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-      closer.close();
-
-      assertEquals(2, logHandler.getStoredLogRecords().size());
-
-      LogRecord record = logHandler.getStoredLogRecords().get(0);
-      assertEquals("Suppressing exception thrown when closing " + c2, record.getMessage());
-
-      record = logHandler.getStoredLogRecords().get(1);
-      assertEquals("Suppressing exception thrown when closing " + c1, record.getMessage());
-    } finally {
-      Closeables.logger.removeHandler(logHandler);
-    }
-  }
-
-  public static void testSuppressingSuppressorIfPossible() throws IOException {
+  public static void testSuppressingSuppressor() throws IOException {
     Closer closer = Closer.create();
-    // can't test the JDK7 suppressor when not running on JDK7
-    if (closer.suppressor instanceof LoggingSuppressor) {
-      return;
-    }
 
     IOException thrownException = new IOException();
     IOException c1Exception = new IOException();
@@ -331,7 +288,7 @@ public class CloserTest extends TestCase {
       } catch (Throwable e) {
         throw closer.rethrow(thrownException, IOException.class);
       } finally {
-        assertThat(getSuppressed(thrownException)).isEmpty();
+        assertThat(thrownException.getSuppressed()).isEmpty();
         closer.close();
       }
     } catch (IOException expected) {
@@ -341,7 +298,7 @@ public class CloserTest extends TestCase {
     assertTrue(c1.isClosed());
     assertTrue(c2.isClosed());
 
-    ImmutableSet<Throwable> suppressed = ImmutableSet.copyOf(getSuppressed(thrownException));
+    ImmutableSet<Throwable> suppressed = ImmutableSet.copyOf(thrownException.getSuppressed());
     assertEquals(2, suppressed.size());
 
     assertEquals(ImmutableSet.of(c1Exception, c2Exception), suppressed);
@@ -353,15 +310,6 @@ public class CloserTest extends TestCase {
     closer.close();
   }
 
-  static Throwable[] getSuppressed(Throwable throwable) {
-    try {
-      Method getSuppressed = Throwable.class.getDeclaredMethod("getSuppressed");
-      return (Throwable[]) getSuppressed.invoke(throwable);
-    } catch (Exception e) {
-      throw new AssertionError(e); // only called if running on JDK7
-    }
-  }
-
   /**
    * Asserts that an exception was thrown when trying to close each of the given throwables and that
    * each such exception was suppressed because of the given thrown exception.
@@ -370,6 +318,7 @@ public class CloserTest extends TestCase {
     assertEquals(ImmutableList.copyOf(expected), suppressor.suppressions);
   }
 
+  // TODO(cpovirk): Just use addSuppressed+getSuppressed now that we can rely on it.
   /** Suppressor that records suppressions. */
   private static class TestSuppressor implements Closer.Suppressor {
 
diff --git a/android/guava/src/com/google/common/io/Closer.java b/android/guava/src/com/google/common/io/Closer.java
index b1512ae14..b947cd099 100644
--- a/android/guava/src/com/google/common/io/Closer.java
+++ b/android/guava/src/com/google/common/io/Closer.java
@@ -24,7 +24,6 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import java.io.Closeable;
 import java.io.IOException;
-import java.lang.reflect.Method;
 import java.util.ArrayDeque;
 import java.util.Deque;
 import java.util.logging.Level;
@@ -33,12 +32,10 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * A {@link Closeable} that collects {@code Closeable} resources and closes them all when it is
- * {@linkplain #close closed}. This is intended to approximately emulate the behavior of Java 7's <a
- * href="http://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html"
- * >try-with-resources</a> statement in JDK6-compatible code. Running on Java 7, code using this
- * should be approximately equivalent in behavior to the same code written with try-with-resources.
- * Running on Java 6, exceptions that cannot be thrown must be logged rather than being added to the
- * thrown exception as a suppressed exception.
+ * {@linkplain #close closed}. This was intended to approximately emulate the behavior of Java 7's
+ * <a href="http://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html"
+ * >try-with-resources</a> statement in JDK6-compatible code. Code using this should be
+ * approximately equivalent in behavior to the same code written with try-with-resources.
  *
  * <p>This class is intended to be used in the following pattern:
  *
@@ -75,14 +72,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  *       another exception is already being thrown) is <i>suppressed</i>.
  * </ul>
  *
- * <p>An exception that is suppressed is not thrown. The method of suppression used depends on the
- * version of Java the code is running on:
- *
- * <ul>
- *   <li><b>Java 7+:</b> Exceptions are suppressed by adding them to the exception that <i>will</i>
- *       be thrown using {@code Throwable.addSuppressed(Throwable)}.
- *   <li><b>Java 6:</b> Exceptions are suppressed by logging them instead.
- * </ul>
+ * <p>An exception that is suppressed is added to the exception that <i>will</i> be thrown using
+ * {@code Throwable.addSuppressed(Throwable)}.
  *
  * @author Colin Decker
  * @since 14.0
@@ -92,18 +83,9 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 @GwtIncompatible
 @ElementTypesAreNonnullByDefault
 public final class Closer implements Closeable {
-
-  /** The suppressor implementation to use for the current Java version. */
-  private static final Suppressor SUPPRESSOR;
-
-  static {
-    SuppressingSuppressor suppressingSuppressor = SuppressingSuppressor.tryCreate();
-    SUPPRESSOR = suppressingSuppressor == null ? LoggingSuppressor.INSTANCE : suppressingSuppressor;
-  }
-
   /** Creates a new {@link Closer}. */
   public static Closer create() {
-    return new Closer(SUPPRESSOR);
+    return new Closer(SUPPRESSING_SUPPRESSOR);
   }
 
   @VisibleForTesting final Suppressor suppressor;
@@ -248,55 +230,27 @@ public final class Closer implements Closeable {
     void suppress(Closeable closeable, Throwable thrown, Throwable suppressed);
   }
 
-  /** Suppresses exceptions by logging them. */
-  @VisibleForTesting
-  static final class LoggingSuppressor implements Suppressor {
-
-    static final LoggingSuppressor INSTANCE = new LoggingSuppressor();
-
-    @Override
-    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
-      // log to the same place as Closeables
-      Closeables.logger.log(
-          Level.WARNING, "Suppressing exception thrown when closing " + closeable, suppressed);
-    }
-  }
-
   /**
-   * Suppresses exceptions by adding them to the exception that will be thrown using JDK7's
+   * Suppresses exceptions by adding them to the exception that will be thrown using the
    * addSuppressed(Throwable) mechanism.
    */
-  @VisibleForTesting
-  static final class SuppressingSuppressor implements Suppressor {
-    @CheckForNull
-    static SuppressingSuppressor tryCreate() {
-      Method addSuppressed;
-      try {
-        addSuppressed = Throwable.class.getMethod("addSuppressed", Throwable.class);
-      } catch (Throwable e) {
-        return null;
-      }
-      return new SuppressingSuppressor(addSuppressed);
-    }
-
-    private final Method addSuppressed;
-
-    private SuppressingSuppressor(Method addSuppressed) {
-      this.addSuppressed = addSuppressed;
-    }
-
-    @Override
-    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
-      // ensure no exceptions from addSuppressed
-      if (thrown == suppressed) {
-        return;
-      }
-      try {
-        addSuppressed.invoke(thrown, suppressed);
-      } catch (Throwable e) {
-        // if, somehow, IllegalAccessException or another exception is thrown, fall back to logging
-        LoggingSuppressor.INSTANCE.suppress(closeable, thrown, suppressed);
-      }
-    }
-  }
+  private static final Suppressor SUPPRESSING_SUPPRESSOR =
+      (closeable, thrown, suppressed) -> {
+        // ensure no exceptions from addSuppressed
+        if (thrown == suppressed) {
+          return;
+        }
+        try {
+          thrown.addSuppressed(suppressed);
+        } catch (Throwable e) {
+          /*
+           * A Throwable is very unlikely, but we really don't want to throw from a Suppressor, so
+           * we catch everything. (Any Exception is either a RuntimeException or
+           * sneaky checked exception.) With no better options, we log anything to the same
+           * place as Closeables logs.
+           */
+          Closeables.logger.log(
+              Level.WARNING, "Suppressing exception thrown when closing " + closeable, suppressed);
+        }
+      };
 }
diff --git a/guava-tests/test/com/google/common/io/ByteSourceTest.java b/guava-tests/test/com/google/common/io/ByteSourceTest.java
index 078b0f98b..3b63728df 100644
--- a/guava-tests/test/com/google/common/io/ByteSourceTest.java
+++ b/guava-tests/test/com/google/common/io/ByteSourceTest.java
@@ -23,6 +23,7 @@ import static com.google.common.io.TestOption.OPEN_THROWS;
 import static com.google.common.io.TestOption.READ_THROWS;
 import static com.google.common.io.TestOption.SKIP_THROWS;
 import static com.google.common.io.TestOption.WRITE_THROWS;
+import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertThrows;
 
@@ -31,9 +32,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.hash.Hashing;
-import com.google.common.io.Closer.LoggingSuppressor;
 import com.google.common.primitives.UnsignedBytes;
-import com.google.common.testing.TestLogHandler;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -378,61 +377,28 @@ public class ByteSourceTest extends IoTestCase {
       ImmutableSet.of(BROKEN_CLOSE_SINK, BROKEN_OPEN_SINK, BROKEN_WRITE_SINK);
 
   public void testCopyExceptions() {
-    if (Closer.create().suppressor instanceof LoggingSuppressor) {
-      // test that exceptions are logged
-
-      TestLogHandler logHandler = new TestLogHandler();
-      Closeables.logger.addHandler(logHandler);
-      try {
-        for (ByteSource in : BROKEN_SOURCES) {
-          runFailureTest(in, newNormalByteSink());
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(in, BROKEN_CLOSE_SINK);
-          assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, getAndResetRecords(logHandler));
-        }
-
-        for (ByteSink out : BROKEN_SINKS) {
-          runFailureTest(newNormalByteSource(), out);
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
+    // test that exceptions are suppressed
 
-          runFailureTest(BROKEN_CLOSE_SOURCE, out);
-          assertEquals(1, getAndResetRecords(logHandler));
-        }
+    for (ByteSource in : BROKEN_SOURCES) {
+      int suppressed = runSuppressionFailureTest(in, newNormalByteSink());
+      assertEquals(0, suppressed);
 
-        for (ByteSource in : BROKEN_SOURCES) {
-          for (ByteSink out : BROKEN_SINKS) {
-            runFailureTest(in, out);
-            assertTrue(getAndResetRecords(logHandler) <= 1);
-          }
-        }
-      } finally {
-        Closeables.logger.removeHandler(logHandler);
-      }
-    } else {
-      // test that exceptions are suppressed
+      suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
+      assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
+    }
 
-      for (ByteSource in : BROKEN_SOURCES) {
-        int suppressed = runSuppressionFailureTest(in, newNormalByteSink());
-        assertEquals(0, suppressed);
+    for (ByteSink out : BROKEN_SINKS) {
+      int suppressed = runSuppressionFailureTest(newNormalByteSource(), out);
+      assertEquals(0, suppressed);
 
-        suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
-        assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
-      }
+      suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
+      assertEquals(1, suppressed);
+    }
 
+    for (ByteSource in : BROKEN_SOURCES) {
       for (ByteSink out : BROKEN_SINKS) {
-        int suppressed = runSuppressionFailureTest(newNormalByteSource(), out);
-        assertEquals(0, suppressed);
-
-        suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
-        assertEquals(1, suppressed);
-      }
-
-      for (ByteSource in : BROKEN_SOURCES) {
-        for (ByteSink out : BROKEN_SINKS) {
-          int suppressed = runSuppressionFailureTest(in, out);
-          assertTrue(suppressed <= 1);
-        }
+        int suppressed = runSuppressionFailureTest(in, out);
+        assertThat(suppressed).isAtMost(1);
       }
     }
   }
@@ -441,20 +407,6 @@ public class ByteSourceTest extends IoTestCase {
     assertEquals(ByteSource.empty(), source.slice(0, 3).slice(4, 3));
   }
 
-  private static int getAndResetRecords(TestLogHandler logHandler) {
-    int records = logHandler.getStoredLogRecords().size();
-    logHandler.clear();
-    return records;
-  }
-
-  private static void runFailureTest(ByteSource in, ByteSink out) {
-    try {
-      in.copyTo(out);
-      fail();
-    } catch (IOException expected) {
-    }
-  }
-
   /**
    * @return the number of exceptions that were suppressed on the expected thrown exception
    */
@@ -463,7 +415,7 @@ public class ByteSourceTest extends IoTestCase {
       in.copyTo(out);
       fail();
     } catch (IOException expected) {
-      return CloserTest.getSuppressed(expected).length;
+      return expected.getSuppressed().length;
     }
     throw new AssertionError(); // can't happen
   }
diff --git a/guava-tests/test/com/google/common/io/CharSourceTest.java b/guava-tests/test/com/google/common/io/CharSourceTest.java
index cf305fd61..e59bfcb64 100644
--- a/guava-tests/test/com/google/common/io/CharSourceTest.java
+++ b/guava-tests/test/com/google/common/io/CharSourceTest.java
@@ -21,14 +21,13 @@ import static com.google.common.io.TestOption.CLOSE_THROWS;
 import static com.google.common.io.TestOption.OPEN_THROWS;
 import static com.google.common.io.TestOption.READ_THROWS;
 import static com.google.common.io.TestOption.WRITE_THROWS;
+import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertThrows;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
-import com.google.common.io.Closer.LoggingSuppressor;
-import com.google.common.testing.TestLogHandler;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.Reader;
@@ -278,76 +277,29 @@ public class CharSourceTest extends IoTestCase {
       ImmutableSet.of(BROKEN_CLOSE_SINK, BROKEN_OPEN_SINK, BROKEN_WRITE_SINK);
 
   public void testCopyExceptions() {
-    if (Closer.create().suppressor instanceof LoggingSuppressor) {
-      // test that exceptions are logged
-
-      TestLogHandler logHandler = new TestLogHandler();
-      Closeables.logger.addHandler(logHandler);
-      try {
-        for (CharSource in : BROKEN_SOURCES) {
-          runFailureTest(in, newNormalCharSink());
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(in, BROKEN_CLOSE_SINK);
-          assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, getAndResetRecords(logHandler));
-        }
-
-        for (CharSink out : BROKEN_SINKS) {
-          runFailureTest(newNormalCharSource(), out);
-          assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-          runFailureTest(BROKEN_CLOSE_SOURCE, out);
-          assertEquals(1, getAndResetRecords(logHandler));
-        }
-
-        for (CharSource in : BROKEN_SOURCES) {
-          for (CharSink out : BROKEN_SINKS) {
-            runFailureTest(in, out);
-            assertTrue(getAndResetRecords(logHandler) <= 1);
-          }
-        }
-      } finally {
-        Closeables.logger.removeHandler(logHandler);
-      }
-    } else {
-      // test that exceptions are suppressed
-
-      for (CharSource in : BROKEN_SOURCES) {
-        int suppressed = runSuppressionFailureTest(in, newNormalCharSink());
-        assertEquals(0, suppressed);
+    // test that exceptions are suppressed
 
-        suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
-        assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
-      }
+    for (CharSource in : BROKEN_SOURCES) {
+      int suppressed = runSuppressionFailureTest(in, newNormalCharSink());
+      assertEquals(0, suppressed);
 
-      for (CharSink out : BROKEN_SINKS) {
-        int suppressed = runSuppressionFailureTest(newNormalCharSource(), out);
-        assertEquals(0, suppressed);
+      suppressed = runSuppressionFailureTest(in, BROKEN_CLOSE_SINK);
+      assertEquals((in == BROKEN_OPEN_SOURCE) ? 0 : 1, suppressed);
+    }
 
-        suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
-        assertEquals(1, suppressed);
-      }
+    for (CharSink out : BROKEN_SINKS) {
+      int suppressed = runSuppressionFailureTest(newNormalCharSource(), out);
+      assertEquals(0, suppressed);
 
-      for (CharSource in : BROKEN_SOURCES) {
-        for (CharSink out : BROKEN_SINKS) {
-          int suppressed = runSuppressionFailureTest(in, out);
-          assertTrue(suppressed <= 1);
-        }
-      }
+      suppressed = runSuppressionFailureTest(BROKEN_CLOSE_SOURCE, out);
+      assertEquals(1, suppressed);
     }
-  }
 
-  private static int getAndResetRecords(TestLogHandler logHandler) {
-    int records = logHandler.getStoredLogRecords().size();
-    logHandler.clear();
-    return records;
-  }
-
-  private static void runFailureTest(CharSource in, CharSink out) {
-    try {
-      in.copyTo(out);
-      fail();
-    } catch (IOException expected) {
+    for (CharSource in : BROKEN_SOURCES) {
+      for (CharSink out : BROKEN_SINKS) {
+        int suppressed = runSuppressionFailureTest(in, out);
+        assertThat(suppressed).isAtMost(1);
+      }
     }
   }
 
@@ -359,7 +311,7 @@ public class CharSourceTest extends IoTestCase {
       in.copyTo(out);
       fail();
     } catch (IOException expected) {
-      return CloserTest.getSuppressed(expected).length;
+      return expected.getSuppressed().length;
     }
     throw new AssertionError(); // can't happen
   }
diff --git a/guava-tests/test/com/google/common/io/CloserTest.java b/guava-tests/test/com/google/common/io/CloserTest.java
index 90c4eefe8..6dce40fda 100644
--- a/guava-tests/test/com/google/common/io/CloserTest.java
+++ b/guava-tests/test/com/google/common/io/CloserTest.java
@@ -25,13 +25,9 @@ import com.google.common.base.Objects;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Lists;
-import com.google.common.io.Closer.LoggingSuppressor;
-import com.google.common.testing.TestLogHandler;
 import java.io.Closeable;
 import java.io.IOException;
-import java.lang.reflect.Method;
 import java.util.List;
-import java.util.logging.LogRecord;
 import junit.framework.TestCase;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -49,11 +45,6 @@ public class CloserTest extends TestCase {
     suppressor = new TestSuppressor();
   }
 
-  @AndroidIncompatible // TODO(cpovirk): Look up Build.VERSION.SDK_INT reflectively.
-  public void testCreate() {
-    assertThat(Closer.create().suppressor).isInstanceOf(Closer.SuppressingSuppressor.class);
-  }
-
   public void testNoExceptionsThrown() throws IOException {
     Closer closer = new Closer(suppressor);
 
@@ -282,42 +273,8 @@ public class CloserTest extends TestCase {
         new Suppression(c1, c3Exception, c1Exception));
   }
 
-  public static void testLoggingSuppressor() throws IOException {
-    TestLogHandler logHandler = new TestLogHandler();
-
-    Closeables.logger.addHandler(logHandler);
-    try {
-      Closer closer = new Closer(new Closer.LoggingSuppressor());
-
-      TestCloseable c1 = closer.register(TestCloseable.throwsOnClose(new IOException()));
-      TestCloseable c2 = closer.register(TestCloseable.throwsOnClose(new RuntimeException()));
-      try {
-        throw closer.rethrow(new IOException("thrown"), IOException.class);
-      } catch (IOException expected) {
-      }
-
-      assertTrue(logHandler.getStoredLogRecords().isEmpty());
-
-      closer.close();
-
-      assertEquals(2, logHandler.getStoredLogRecords().size());
-
-      LogRecord record = logHandler.getStoredLogRecords().get(0);
-      assertEquals("Suppressing exception thrown when closing " + c2, record.getMessage());
-
-      record = logHandler.getStoredLogRecords().get(1);
-      assertEquals("Suppressing exception thrown when closing " + c1, record.getMessage());
-    } finally {
-      Closeables.logger.removeHandler(logHandler);
-    }
-  }
-
-  public static void testSuppressingSuppressorIfPossible() throws IOException {
+  public static void testSuppressingSuppressor() throws IOException {
     Closer closer = Closer.create();
-    // can't test the JDK7 suppressor when not running on JDK7
-    if (closer.suppressor instanceof LoggingSuppressor) {
-      return;
-    }
 
     IOException thrownException = new IOException();
     IOException c1Exception = new IOException();
@@ -331,7 +288,7 @@ public class CloserTest extends TestCase {
       } catch (Throwable e) {
         throw closer.rethrow(thrownException, IOException.class);
       } finally {
-        assertThat(getSuppressed(thrownException)).isEmpty();
+        assertThat(thrownException.getSuppressed()).isEmpty();
         closer.close();
       }
     } catch (IOException expected) {
@@ -341,7 +298,7 @@ public class CloserTest extends TestCase {
     assertTrue(c1.isClosed());
     assertTrue(c2.isClosed());
 
-    ImmutableSet<Throwable> suppressed = ImmutableSet.copyOf(getSuppressed(thrownException));
+    ImmutableSet<Throwable> suppressed = ImmutableSet.copyOf(thrownException.getSuppressed());
     assertEquals(2, suppressed.size());
 
     assertEquals(ImmutableSet.of(c1Exception, c2Exception), suppressed);
@@ -353,15 +310,6 @@ public class CloserTest extends TestCase {
     closer.close();
   }
 
-  static Throwable[] getSuppressed(Throwable throwable) {
-    try {
-      Method getSuppressed = Throwable.class.getDeclaredMethod("getSuppressed");
-      return (Throwable[]) getSuppressed.invoke(throwable);
-    } catch (Exception e) {
-      throw new AssertionError(e); // only called if running on JDK7
-    }
-  }
-
   /**
    * Asserts that an exception was thrown when trying to close each of the given throwables and that
    * each such exception was suppressed because of the given thrown exception.
@@ -370,6 +318,7 @@ public class CloserTest extends TestCase {
     assertEquals(ImmutableList.copyOf(expected), suppressor.suppressions);
   }
 
+  // TODO(cpovirk): Just use addSuppressed+getSuppressed now that we can rely on it.
   /** Suppressor that records suppressions. */
   private static class TestSuppressor implements Closer.Suppressor {
 
diff --git a/guava/src/com/google/common/io/Closer.java b/guava/src/com/google/common/io/Closer.java
index b1512ae14..b947cd099 100644
--- a/guava/src/com/google/common/io/Closer.java
+++ b/guava/src/com/google/common/io/Closer.java
@@ -24,7 +24,6 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import java.io.Closeable;
 import java.io.IOException;
-import java.lang.reflect.Method;
 import java.util.ArrayDeque;
 import java.util.Deque;
 import java.util.logging.Level;
@@ -33,12 +32,10 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * A {@link Closeable} that collects {@code Closeable} resources and closes them all when it is
- * {@linkplain #close closed}. This is intended to approximately emulate the behavior of Java 7's <a
- * href="http://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html"
- * >try-with-resources</a> statement in JDK6-compatible code. Running on Java 7, code using this
- * should be approximately equivalent in behavior to the same code written with try-with-resources.
- * Running on Java 6, exceptions that cannot be thrown must be logged rather than being added to the
- * thrown exception as a suppressed exception.
+ * {@linkplain #close closed}. This was intended to approximately emulate the behavior of Java 7's
+ * <a href="http://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html"
+ * >try-with-resources</a> statement in JDK6-compatible code. Code using this should be
+ * approximately equivalent in behavior to the same code written with try-with-resources.
  *
  * <p>This class is intended to be used in the following pattern:
  *
@@ -75,14 +72,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  *       another exception is already being thrown) is <i>suppressed</i>.
  * </ul>
  *
- * <p>An exception that is suppressed is not thrown. The method of suppression used depends on the
- * version of Java the code is running on:
- *
- * <ul>
- *   <li><b>Java 7+:</b> Exceptions are suppressed by adding them to the exception that <i>will</i>
- *       be thrown using {@code Throwable.addSuppressed(Throwable)}.
- *   <li><b>Java 6:</b> Exceptions are suppressed by logging them instead.
- * </ul>
+ * <p>An exception that is suppressed is added to the exception that <i>will</i> be thrown using
+ * {@code Throwable.addSuppressed(Throwable)}.
  *
  * @author Colin Decker
  * @since 14.0
@@ -92,18 +83,9 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 @GwtIncompatible
 @ElementTypesAreNonnullByDefault
 public final class Closer implements Closeable {
-
-  /** The suppressor implementation to use for the current Java version. */
-  private static final Suppressor SUPPRESSOR;
-
-  static {
-    SuppressingSuppressor suppressingSuppressor = SuppressingSuppressor.tryCreate();
-    SUPPRESSOR = suppressingSuppressor == null ? LoggingSuppressor.INSTANCE : suppressingSuppressor;
-  }
-
   /** Creates a new {@link Closer}. */
   public static Closer create() {
-    return new Closer(SUPPRESSOR);
+    return new Closer(SUPPRESSING_SUPPRESSOR);
   }
 
   @VisibleForTesting final Suppressor suppressor;
@@ -248,55 +230,27 @@ public final class Closer implements Closeable {
     void suppress(Closeable closeable, Throwable thrown, Throwable suppressed);
   }
 
-  /** Suppresses exceptions by logging them. */
-  @VisibleForTesting
-  static final class LoggingSuppressor implements Suppressor {
-
-    static final LoggingSuppressor INSTANCE = new LoggingSuppressor();
-
-    @Override
-    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
-      // log to the same place as Closeables
-      Closeables.logger.log(
-          Level.WARNING, "Suppressing exception thrown when closing " + closeable, suppressed);
-    }
-  }
-
   /**
-   * Suppresses exceptions by adding them to the exception that will be thrown using JDK7's
+   * Suppresses exceptions by adding them to the exception that will be thrown using the
    * addSuppressed(Throwable) mechanism.
    */
-  @VisibleForTesting
-  static final class SuppressingSuppressor implements Suppressor {
-    @CheckForNull
-    static SuppressingSuppressor tryCreate() {
-      Method addSuppressed;
-      try {
-        addSuppressed = Throwable.class.getMethod("addSuppressed", Throwable.class);
-      } catch (Throwable e) {
-        return null;
-      }
-      return new SuppressingSuppressor(addSuppressed);
-    }
-
-    private final Method addSuppressed;
-
-    private SuppressingSuppressor(Method addSuppressed) {
-      this.addSuppressed = addSuppressed;
-    }
-
-    @Override
-    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
-      // ensure no exceptions from addSuppressed
-      if (thrown == suppressed) {
-        return;
-      }
-      try {
-        addSuppressed.invoke(thrown, suppressed);
-      } catch (Throwable e) {
-        // if, somehow, IllegalAccessException or another exception is thrown, fall back to logging
-        LoggingSuppressor.INSTANCE.suppress(closeable, thrown, suppressed);
-      }
-    }
-  }
+  private static final Suppressor SUPPRESSING_SUPPRESSOR =
+      (closeable, thrown, suppressed) -> {
+        // ensure no exceptions from addSuppressed
+        if (thrown == suppressed) {
+          return;
+        }
+        try {
+          thrown.addSuppressed(suppressed);
+        } catch (Throwable e) {
+          /*
+           * A Throwable is very unlikely, but we really don't want to throw from a Suppressor, so
+           * we catch everything. (Any Exception is either a RuntimeException or
+           * sneaky checked exception.) With no better options, we log anything to the same
+           * place as Closeables logs.
+           */
+          Closeables.logger.log(
+              Level.WARNING, "Suppressing exception thrown when closing " + closeable, suppressed);
+        }
+      };
 }