nit: spotbugs fixes for the highest priority warnings

plugins/org.eclipse.mat.hprof/src/org/eclipse/mat/hprof/Pass1Parser.java

@@ -680,9 +680,9 @@ private void readClassDump(long segmentStartPos) throws IOException
             statics[si++] = new Field("<signers>", Type.OBJECT, signersId == 0 ? null : new ObjectReference(null, signersId)); //$NON-NLS-1$
             statics[si++] = new Field("<protectionDomain>", Type.OBJECT, protectionDomainId == 0 ? null : new ObjectReference(null, protectionDomainId)); //$NON-NLS-1$
             if (reserved1Id != 0)
-                statics[si++] = new Field("<reserved1>", Type.OBJECT, reserved1Id == 0 ? null : new ObjectReference(null, reserved1Id)); //$NON-NLS-1$
+                statics[si++] = new Field("<reserved1>", Type.OBJECT, new ObjectReference(null, reserved1Id)); //$NON-NLS-1$
             if (reserved2Id != 0)
-                statics[si++] = new Field("<reserved2>", Type.OBJECT, reserved2Id == 0 ? null : new ObjectReference(null, reserved2Id)); //$NON-NLS-1$
+                statics[si++] = new Field("<reserved2>", Type.OBJECT, new ObjectReference(null, reserved2Id)); //$NON-NLS-1$
             Field all[] = new Field[statics.length + constantPool.length];
             System.arraycopy(statics,  0,  all,  0,  statics.length);
             System.arraycopy(constantPool,  0,  all,  statics.length, constantPool.length);

plugins/org.eclipse.mat.parser/src/org/eclipse/mat/parser/internal/snapshot/ObjectMarker.java

@@ -117,7 +117,7 @@ public long markMultiThreadedInner(int threads) throws InterruptedException
 
         ForkJoinPool pool = new ForkJoinPool(threads);
         try {
-            ObjectMarkerRootCC root = new ObjectMarkerRootCC(null, claimedRoots, bitField, LEVELS_RUN_INLINE, count);
+            ObjectMarkerRootCC root = new ObjectMarkerRootCC(claimedRoots, bitField, LEVELS_RUN_INLINE, count);
             // blocks until all work is done
             pool.invoke(root);
         }
@@ -141,8 +141,8 @@ final class ObjectMarkerRootCC extends CountedCompleter<Void> {
         final int levelsInline;
         final LongAdder count;
 
-        ObjectMarkerRootCC(CountedCompleter<?> parent, int[] roots, ConcurrentBitField visited, int levelsInline, LongAdder count) {
-            super(parent);
+        ObjectMarkerRootCC(int[] roots, ConcurrentBitField visited, int levelsInline, LongAdder count) {
+            super();
             this.roots = roots;
             this.visited = visited;
             this.levelsInline = levelsInline;

plugins/org.eclipse.mat.report/src/org/eclipse/mat/report/SpecFactory.java

@@ -192,6 +192,9 @@ private static final Spec read(InputStream input, Bundle bundle, Object source)
             parserFactory.setNamespaceAware(true);
             // Add schema validation
             URL url = ReportPlugin.getDefault().getBundle().getResource("schema/report.xsd"); //$NON-NLS-1$
+            if (url == null) {
+                throw new IOException("Schema resource not found in bundle: schema/report.xsd"); //$NON-NLS-1$
+            }
             SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
             Schema schema = factory.newSchema(url);
             parserFactory.setSchema(schema);

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/CreateCollectionDump.java

@@ -174,10 +174,9 @@ public static void main(String[] args) throws Exception
         System.out.println("Acquire Heap Dump NOW (then press any key to terminate program)");
         int c = System.in.read();
         // Control-break causes read to return early, so try again for another
-        // key to wait
-        // for the dump to complete
+        // key to wait for the dump to complete
         if (c == -1)
-            c = System.in.read();
+            System.in.read();
 
         cd.print();
     }

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/acquire/AcquireDumpTest.java

@@ -508,7 +508,7 @@ void fillAdders()
 
         doubleAdderValues = new DoubleAdder[2];
         doubleAdderValues[0] = new DoubleAdder();
-        doubleAdderValues[0].add(3.14159);
+        doubleAdderValues[0].add(Math.PI);
         doubleAdderValues[1] = new DoubleAdder();
     }
 
@@ -551,15 +551,15 @@ void checkDoubleAdderResolver(ISnapshot snapshot) throws SnapshotException
         IResult result = query.execute(new VoidProgressListener());
         assertNotNull(result);
         IResultTable table = (IResultTable) result;
-        boolean found3_14159 = false;
+        boolean found_pi = false;
         for (int i = 0; i < table.getRowCount(); ++i)
         {
             Object row = table.getRow(i);
             String val = (String) table.getColumnValue(row, 0);
-            if (Double.toString(3.14159).equals(val))
-                found3_14159 = true;
+            if (Double.toString(Math.PI).equals(val))
+                found_pi = true;
         }
-        assertTrue("DoubleAdder with sum 3.14159 should be resolved", found3_14159); //$NON-NLS-1$
+        assertTrue("DoubleAdder with sum 3.14159 should be resolved", found_pi); //$NON-NLS-1$
     }
 
     BigDecimal values[];

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/ArrayIntTest.java

@@ -25,6 +25,7 @@
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.ArrayInt;
 import org.eclipse.mat.collect.IteratorInt;
@@ -47,7 +48,7 @@ public class ArrayIntTest
      */
     @Test
     public void testArrayInt0() {
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         for (int i = 0; i < COUNT; ++i) {
             int t = 0;
             ArrayInt ss = new ArrayInt(r.nextInt(INITIAL_SIZE));

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/ArrayLongTest.java

@@ -26,6 +26,7 @@
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.ArrayLong;
 import org.eclipse.mat.collect.IteratorLong;
@@ -48,7 +49,7 @@ public class ArrayLongTest
      */
     @Test
     public void testArrayLong0() {
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         for (int i = 0; i < COUNT; ++i) {
             int t = 0;
             ArrayLong ss = new ArrayLong(r.nextInt(INITIAL_SIZE));

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/CompressedArraysTest.java

@@ -16,6 +16,7 @@
 import static org.junit.Assert.assertEquals;
 
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.ArrayIntCompressed;
 import org.eclipse.mat.collect.ArrayLongCompressed;
@@ -28,7 +29,7 @@ public class CompressedArraysTest
     @Test
     public void testIntArrayCompressed()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int INTS = 1024;
         int TESTS = 10;
         for (int i = 1; i <= INTS; i++)
@@ -55,7 +56,7 @@ public void testIntArrayCompressed()
     @Test
     public void testLongArrayCompressed()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int LONGS = 1024;
         int TESTS = 10;
         for (int i = 1; i <= LONGS; i++)
@@ -85,7 +86,7 @@ public void testLongArrayCompressed()
     @Test
     public void testIntAndLongArrayCompressed()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int INTS = 1024;
         int TESTS = 10;
         for (int i = 1; i <= INTS; i++)
@@ -116,7 +117,7 @@ public void testIntAndLongArrayCompressed()
     @Test
     public void testLongAndIntArrayCompressed()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int INTS = 1024;
         int TESTS = 10;
         for (int i = 1; i <= INTS; i++)
@@ -147,7 +148,7 @@ public void testLongAndIntArrayCompressed()
     @Test
     public void testIntArrayCompressedOverwrite()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int INTS = 100;
         for (int i = 1; i <= INTS; i++)
         {
@@ -218,7 +219,7 @@ public void testIntArrayCompressedOverwrite()
     @Test
     public void testLongArrayCompressedOverwrite()
     {
-        Random rand = new Random(SEED);
+        Random rand = ThreadLocalRandom.current();
         int LONGS = 100;
         for (int i = 1; i <= LONGS; i++)
         {

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/QueueIntTest.java

@@ -25,6 +25,7 @@
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.QueueInt;
 import org.eclipse.mat.collect.IteratorInt;
@@ -47,7 +48,7 @@ public class QueueIntTest
      */
     @Test
     public void testQueueInt0() {
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         for (int i = 0; i < COUNT; ++i) {
             int t = 0;
             QueueInt ss = new QueueInt(r.nextInt(INITIAL_SIZE));

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/SetIntTest.java

@@ -25,6 +25,7 @@
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.IteratorInt;
 import org.eclipse.mat.collect.SetInt;
@@ -47,7 +48,7 @@ public class SetIntTest
      */
     @Test
     public void testSetInt0() {
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         for (int i = 0; i < COUNT; ++i) {
             int t = 0;
             SetInt ss = new SetInt(r.nextInt(INITIAL_SIZE));

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/SetLongTest.java

@@ -25,6 +25,7 @@
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.IteratorLong;
 import org.eclipse.mat.collect.SetLong;
@@ -47,7 +48,7 @@ public class SetLongTest
      */
     @Test
     public void testSetLong0() {
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         for (int i = 0; i < COUNT; ++i) {
             int t = 0;
             SetLong ss = new SetLong(r.nextInt(INITIAL_SIZE));

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/collect/SortTest.java

@@ -17,6 +17,7 @@
 
 import java.util.Arrays;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.collect.ArrayUtils;
 import org.junit.Test;
@@ -55,7 +56,7 @@ public void testSort()
     {
         // Generate random data
         int n = longTest ? 29792349 : SHORTTEST;
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         int[] key0 = new int[n];
         int[] key = new int[n];
         int[] value = new int[n];
@@ -198,7 +199,7 @@ public void testSort5()
     {
         // Generate random data
         int n = longTest ? 29792349 : SHORTTEST;
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         int k = n;
         int[] key0 = new int[n];
         int[] key = new int[n];
@@ -223,7 +224,7 @@ public void testSort5()
     public void testSortDesc()
     {
         int n = longTest ? 29792349 : SHORTTEST;
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         long[] key0 = new long[n];
         long[] key = new long[n];
         int[] value = new int[n];
@@ -363,7 +364,7 @@ public void testSortDesc4()
     public void testSortDesc5()
     {
         int n = longTest ? 29792349 : SHORTTEST;
-        Random r = new Random(1);
+        Random r = ThreadLocalRandom.current();
         long[] key0 = new long[n];
         long[] key = new long[n];
         int[] value = new int[n];

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/parser/GzipTests.java

@@ -28,11 +28,13 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 import java.util.function.Supplier;
 import java.util.zip.Deflater;
 import java.util.zip.GZIPInputStream;
 import java.util.zip.GZIPOutputStream;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.eclipse.mat.hprof.ChunkedGZIPRandomAccessFile;
 import org.eclipse.mat.hprof.GZIPInputStream2;
 import org.eclipse.mat.hprof.SeekableStream;
@@ -70,6 +72,7 @@ public GzipTests(int comp)
         this.comp = comp;
     }
 
+    @SuppressFBWarnings(value = "DMI_RANDOM_USED_ONLY_ONCE", justification = "Random is used with fixed seeds to assert test data consistency")
     static byte[] randomText(int size)
     {
         Random rn = new Random(1);
@@ -197,7 +200,7 @@ public void test1() throws IOException
         try (ByteArrayInputStream bis = new ByteArrayInputStream(bo, 0, bol))
         {
             try (InflaterInputStream inf = new InflaterInputStream(bis, false)) {
-                Random r = new Random(1);
+                Random r = ThreadLocalRandom.current();
                 byte bo2[] = new byte[inputLen];
                 int MAXMARK = 32211;
                 int mark = -1;
@@ -293,6 +296,7 @@ public InputStream get()
         checkSeekableStream(b, ss);
     }
 
+    @SuppressFBWarnings(value = "DMI_RANDOM_USED_ONLY_ONCE", justification = "Random is used with fixed seeds to assert test data consistency")
     private void checkSeekableStream(byte[] b, SeekableStream ss) throws IOException
     {
         int inputLen = b.length;

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/parser/TestIndex.java

@@ -21,6 +21,7 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.eclipse.mat.parser.index.IIndexReader.IOne2ManyIndex;
 import org.eclipse.mat.parser.index.IIndexReader.IOne2ManyObjectsIndex;
@@ -212,7 +213,7 @@ public void storeKey(int index, Serializable key)
     public void testLong() throws IOException
     {
         assumeTrue((long) M * N < MAXELEMENTS);
-        Random r = new Random();
+        Random r = ThreadLocalRandom.current();
         long ii[][] = new long[P + 1][];
         for (int p = 0; p < P + 1; p++)
         {

plugins/org.eclipse.mat.tests/src/org/eclipse/mat/tests/parser/TestIndex1to1.java

@@ -23,6 +23,7 @@
 import java.util.Collection;
 import java.util.Random;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.eclipse.mat.collect.IteratorInt;
 import org.eclipse.mat.collect.IteratorLong;
 import org.eclipse.mat.parser.index.IIndexReader;
@@ -38,7 +39,7 @@
 import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameters;
 
-
+@SuppressFBWarnings(value = "DMI_RANDOM_USED_ONLY_ONCE", justification = "Random is used with fixed seeds to assert test data consistency")
 @RunWith(value = Parameterized.class)
 public class TestIndex1to1
 {