8211936: Better String parsing

Co-authored-by: Joe Darcy <joe.darcy@oracle.com>
Co-authored-by: Paul Hohensee <hohensee@amazon.com>
Reviewed-by: bpb, darcy

src/java.base/share/classes/java/math/BigDecimal.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -3414,9 +3414,32 @@ public class BigDecimal extends Number implements Comparable<BigDecimal> {
      */
     @Override
     public long longValue(){
-        return (intCompact != INFLATED && scale == 0) ?
+        if (intCompact != INFLATED && scale == 0) {
-            intCompact:
+            return intCompact;
-            toBigInteger().longValue();
+        } else {
+            // Fastpath zero and small values
+            if (this.signum() == 0 || fractionOnly() ||
+                // Fastpath very large-scale values that will result
+                // in a truncated value of zero. If the scale is -64
+                // or less, there are at least 64 powers of 10 in the
+                // value of the numerical result. Since 10 = 2*5, in
+                // that case there would also be 64 powers of 2 in the
+                // result, meaning all 64 bits of a long will be zero.
+                scale <= -64) {
+                return 0;
+            } else {
+                return toBigInteger().longValue();
+            }
+        }
+    }
+
+    /**
+     * Return true if a nonzero BigDecimal has an absolute value less
+     * than one; i.e. only has fraction digits.
+     */
+    private boolean fractionOnly() {
+        assert this.signum() != 0;
+        return (this.precision() - this.scale) <= 0;
     }
 
     /**
@@ -3434,15 +3457,20 @@ public class BigDecimal extends Number implements Comparable<BigDecimal> {
     public long longValueExact() {
         if (intCompact != INFLATED && scale == 0)
             return intCompact;
+
+        // Fastpath zero
+        if (this.signum() == 0)
+            return 0;
+
+        // Fastpath numbers less than 1.0 (the latter can be very slow
+        // to round if very small)
+        if (fractionOnly())
+            throw new ArithmeticException("Rounding necessary");
+
         // If more than 19 digits in integer part it cannot possibly fit
         if ((precision() - scale) > 19) // [OK for negative scale too]
             throw new java.lang.ArithmeticException("Overflow");
-        // Fastpath zero and < 1.0 numbers (the latter can be very slow
+
-        // to round if very small)
-        if (this.signum() == 0)
-            return 0;
-        if ((this.precision() - this.scale) <= 0)
-            throw new ArithmeticException("Rounding necessary");
         // round to an integer, with Exception if decimal part non-0
         BigDecimal num = this.setScale(0, ROUND_UNNECESSARY);
         if (num.precision() >= 19) // need to check carefully
@@ -3486,7 +3514,7 @@ public class BigDecimal extends Number implements Comparable<BigDecimal> {
     public int intValue() {
         return  (intCompact != INFLATED && scale == 0) ?
             (int)intCompact :
-            toBigInteger().intValue();
+            (int)longValue();
     }
 
     /**

test/jdk/java/math/BigDecimal/IntValueExactTests.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8211936
+ * @summary Tests of BigDecimal.intValueExact
+ */
+import java.math.*;
+import java.util.List;
+import java.util.Map;
+import static java.util.Map.entry;
+
+public class IntValueExactTests {
+    public static void main(String... args) {
+        int failures = 0;
+
+        failures += intValueExactSuccessful();
+        failures += intValueExactExceptional();
+
+        if (failures > 0) {
+            throw new RuntimeException("Incurred " + failures +
+                                       " failures while testing intValueExact.");
+        }
+    }
+
+    private static int simpleIntValueExact(BigDecimal bd) {
+        return bd.toBigIntegerExact().intValue();
+    }
+
+    private static int intValueExactSuccessful() {
+        int failures = 0;
+
+        // Strings used to create BigDecimal instances on which invoking
+        // intValueExact() will succeed.
+        Map<BigDecimal, Integer> successCases =
+            Map.ofEntries(entry(new BigDecimal("2147483647"),    Integer.MAX_VALUE), // 2^31 -1
+                          entry(new BigDecimal("2147483647.0"),  Integer.MAX_VALUE),
+                          entry(new BigDecimal("2147483647.00"), Integer.MAX_VALUE),
+
+                          entry(new BigDecimal("-2147483648"),   Integer.MIN_VALUE), // -2^31
+                          entry(new BigDecimal("-2147483648.0"), Integer.MIN_VALUE),
+                          entry(new BigDecimal("-2147483648.00"),Integer.MIN_VALUE),
+
+                          entry(new BigDecimal("1e0"),    1),
+                          entry(new BigDecimal(BigInteger.ONE, -9),   1_000_000_000),
+
+                          entry(new BigDecimal("0e13"),   0), // Fast path zero
+                          entry(new BigDecimal("0e32"),   0),
+                          entry(new BigDecimal("0e512"), 0),
+
+                          entry(new BigDecimal("10.000000000000000000000000000000000"), 10));
+
+        for (var testCase : successCases.entrySet()) {
+            BigDecimal bd = testCase.getKey();
+            int expected = testCase.getValue();
+            try {
+                int intValueExact = bd.intValueExact();
+                if (expected != intValueExact ||
+                    intValueExact != simpleIntValueExact(bd)) {
+                    failures++;
+                    System.err.println("Unexpected intValueExact result " + intValueExact +
+                                       " on " + bd);
+                }
+            } catch (Exception e) {
+                failures++;
+                System.err.println("Error on " + bd + "\tException message:" + e.getMessage());
+            }
+        }
+        return failures;
+    }
+
+    private static int intValueExactExceptional() {
+        int failures = 0;
+        List<BigDecimal> exceptionalCases =
+            List.of(new BigDecimal("2147483648"), // Integer.MAX_VALUE + 1
+                    new BigDecimal("2147483648.0"),
+                    new BigDecimal("2147483648.00"),
+                    new BigDecimal("-2147483649"), // Integer.MIN_VALUE - 1
+                    new BigDecimal("-2147483649.1"),
+                    new BigDecimal("-2147483649.01"),
+
+                    new BigDecimal("9999999999999999999999999999999"),
+                    new BigDecimal("10000000000000000000000000000000"),
+
+                    new BigDecimal("0.99"),
+                    new BigDecimal("0.999999999999999999999"));
+
+        for (BigDecimal bd : exceptionalCases) {
+            try {
+                int intValueExact = bd.intValueExact();
+                failures++;
+                System.err.println("Unexpected non-exceptional intValueExact on " + bd);
+            } catch (ArithmeticException e) {
+                // Success;
+            }
+        }
+        return failures;
+    }
+}

test/jdk/java/math/BigDecimal/IntegralValueTests.java

@@ -0,0 +1,241 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8211936
+ * @summary Tests of BigDecimal.intValue() and BigDecimal.longValue()
+ */
+import java.math.BigDecimal;
+import java.util.Map;
+
+public class IntegralValueTests {
+    public static void main(String... args) {
+        int failures =
+            integralValuesTest(INT_VALUES, true) +
+            integralValuesTest(LONG_VALUES, false);
+        if (failures != 0) {
+            throw new RuntimeException
+                ("Incurred " + failures + " failures for {int,long}Value().");
+        }
+    }
+
+    private static final Map<BigDecimal, Number> INT_VALUES =
+        Map.ofEntries(
+
+         // 2**31 - 1
+         Map.entry(new BigDecimal("2147483647"), Integer.MAX_VALUE),
+         Map.entry(new BigDecimal("2147483647.0"), Integer.MAX_VALUE),
+         Map.entry(new BigDecimal("2147483647.00"), Integer.MAX_VALUE),
+
+         Map.entry(new BigDecimal("-2147483647"), -Integer.MAX_VALUE),
+         Map.entry(new BigDecimal("-2147483647.0"), -Integer.MAX_VALUE),
+
+         // -2**31
+         Map.entry(new BigDecimal("-2147483648"), Integer.MIN_VALUE),
+         Map.entry(new BigDecimal("-2147483648.1"), Integer.MIN_VALUE),
+         Map.entry(new BigDecimal("-2147483648.01"), Integer.MIN_VALUE),
+
+         // -2**31 + 1 truncation to 2**31 - 1
+         Map.entry(new BigDecimal("-2147483649"), Integer.MAX_VALUE),
+
+         // 2**64 - 1 truncation to 1
+         Map.entry(new BigDecimal("4294967295"), -1),
+
+         // 2**64 truncation to 0
+         Map.entry(new BigDecimal("4294967296"), 0),
+
+         // Fast path truncation to 0
+         Map.entry(new BigDecimal("1e32"), 0),
+
+         // Slow path truncation to -2**31
+         Map.entry(new BigDecimal("1e31"), Integer.MIN_VALUE),
+
+         // Slow path
+         Map.entry(new BigDecimal("1e0"), 1),
+
+         // Fast path round to 0
+         Map.entry(new BigDecimal("9e-1"), 0),
+
+         // Some random values
+         Map.entry(new BigDecimal("900e-1"), 90), // Increasing negative exponents
+         Map.entry(new BigDecimal("900e-2"), 9),
+         Map.entry(new BigDecimal("900e-3"), 0),
+
+         // Fast path round to 0
+         Map.entry(new BigDecimal("123456789e-9"), 0),
+
+         // Slow path round to 1
+         Map.entry(new BigDecimal("123456789e-8"), 1),
+
+         // Increasing positive exponents
+         Map.entry(new BigDecimal("10000001e1"), 100000010),
+         Map.entry(new BigDecimal("10000001e10"), -1315576832),
+         Map.entry(new BigDecimal("10000001e100"), 0),
+         Map.entry(new BigDecimal("10000001e1000"), 0),
+         Map.entry(new BigDecimal("10000001e10000"), 0),
+         Map.entry(new BigDecimal("10000001e100000"), 0),
+         Map.entry(new BigDecimal("10000001e1000000"), 0),
+         Map.entry(new BigDecimal("10000001e10000000"), 0),
+         Map.entry(new BigDecimal("10000001e100000000"), 0),
+         Map.entry(new BigDecimal("10000001e1000000000"), 0),
+
+         // Increasing negative exponents
+         Map.entry(new BigDecimal("10000001e-1"), 1000000),
+         Map.entry(new BigDecimal("10000001e-10"), 0),
+         Map.entry(new BigDecimal("10000001e-100"), 0),
+         Map.entry(new BigDecimal("10000001e-1000"), 0),
+         Map.entry(new BigDecimal("10000001e-10000"), 0),
+         Map.entry(new BigDecimal("10000001e-100000"), 0),
+         Map.entry(new BigDecimal("10000001e-1000000"), 0),
+         Map.entry(new BigDecimal("10000001e-10000000"), 0),
+         Map.entry(new BigDecimal("10000001e-100000000"), 0),
+         Map.entry(new BigDecimal("10000001e-1000000000"), 0),
+
+         // Currency calculation to 4 places
+         Map.entry(new BigDecimal("12345.0001"), 12345),
+         Map.entry(new BigDecimal("12345.9999"), 12345),
+         Map.entry(new BigDecimal("-12345.0001"), -12345),
+         Map.entry(new BigDecimal("-12345.9999"), -12345));
+
+    private static final Map<BigDecimal, Number> LONG_VALUES =
+        Map.ofEntries(
+         // 2**63 - 1
+         Map.entry(new BigDecimal("9223372036854775807"), Long.MAX_VALUE),
+         Map.entry(new BigDecimal("9223372036854775807.0"), Long.MAX_VALUE),
+         Map.entry(new BigDecimal("9223372036854775807.00"), Long.MAX_VALUE),
+
+         // 2**63 truncation to -2**63
+         Map.entry(new BigDecimal("-9223372036854775808"), Long.MIN_VALUE),
+         Map.entry(new BigDecimal("-9223372036854775808.1"), Long.MIN_VALUE),
+         Map.entry(new BigDecimal("-9223372036854775808.01"), Long.MIN_VALUE),
+
+         // -2**63 + 1 truncation to 2**63 - 1
+         Map.entry(new BigDecimal("-9223372036854775809"), 9223372036854775807L),
+
+         // 2**64 - 1 truncation to -1
+         Map.entry(new BigDecimal("18446744073709551615"), -1L),
+
+         // 2**64 truncation to 0
+         Map.entry(new BigDecimal("18446744073709551616"), 0L),
+
+         // Slow path truncation to -2**63
+         Map.entry(new BigDecimal("1e63"),  -9223372036854775808L),
+         Map.entry(new BigDecimal("-1e63"), -9223372036854775808L),
+         // Fast path with larger magnitude scale
+         Map.entry(new BigDecimal("1e64"), 0L),
+         Map.entry(new BigDecimal("-1e64"), 0L),
+         Map.entry(new BigDecimal("1e65"), 0L),
+         Map.entry(new BigDecimal("-1e65"), 0L),
+
+         // Slow path
+         Map.entry(new BigDecimal("1e0"), 1L),
+
+         // Fast path round to 0
+         Map.entry(new BigDecimal("9e-1"), 0L),
+
+         // Some random values
+         Map.entry(new BigDecimal("900e-1"), 90L), // Increasing negative exponents
+         Map.entry(new BigDecimal("900e-2"), 9L),
+         Map.entry(new BigDecimal("900e-3"), 0L),
+
+         // Fast path round to 0
+         Map.entry(new BigDecimal("123456789e-9"), 0L),
+
+         // Slow path round to 1
+         Map.entry(new BigDecimal("123456789e-8"), 1L),
+
+         // Increasing positive exponents
+         Map.entry(new BigDecimal("10000001e1"), 100000010L),
+         Map.entry(new BigDecimal("10000001e10"), 100000010000000000L),
+         Map.entry(new BigDecimal("10000001e100"), 0L),
+         Map.entry(new BigDecimal("10000001e1000"), 0L),
+         Map.entry(new BigDecimal("10000001e10000"), 0L),
+         Map.entry(new BigDecimal("10000001e100000"), 0L),
+         Map.entry(new BigDecimal("10000001e1000000"), 0L),
+         Map.entry(new BigDecimal("10000001e10000000"), 0L),
+         Map.entry(new BigDecimal("10000001e100000000"), 0L),
+         Map.entry(new BigDecimal("10000001e1000000000"), 0L),
+
+         // Increasing negative exponents
+         Map.entry(new BigDecimal("10000001e-1"), 1000000L),
+         Map.entry(new BigDecimal("10000001e-10"), 0L),
+         Map.entry(new BigDecimal("10000001e-100"), 0L),
+         Map.entry(new BigDecimal("10000001e-1000"), 0L),
+         Map.entry(new BigDecimal("10000001e-10000"), 0L),
+         Map.entry(new BigDecimal("10000001e-100000"), 0L),
+         Map.entry(new BigDecimal("10000001e-1000000"), 0L),
+         Map.entry(new BigDecimal("10000001e-10000000"), 0L),
+         Map.entry(new BigDecimal("10000001e-100000000"), 0L),
+         Map.entry(new BigDecimal("10000001e-1000000000"), 0L),
+
+         // Currency calculation to 4 places
+         Map.entry(new BigDecimal("12345.0001"), 12345L),
+         Map.entry(new BigDecimal("12345.9999"), 12345L),
+         Map.entry(new BigDecimal("-12345.0001"), -12345L),
+         Map.entry(new BigDecimal("-12345.9999"), -12345L));
+
+    private static int integralValuesTest(Map<BigDecimal, Number> v, boolean isInt) {
+        System.err.format("Testing %s%n", isInt ? "Integer" : "Long");
+        int failures = 0;
+        for (var testCase : v.entrySet()) {
+            BigDecimal bd = testCase.getKey();
+            Number expected = testCase.getValue();
+            try {
+                if (isInt) {
+                    int intValue = bd.intValue();
+                    if (intValue != (int)expected) {
+                        failures += reportError(bd, expected, intValue, isInt);
+                    }
+                } else {
+                    long longValue = bd.longValue();
+                    if (longValue != (long)expected) {
+                        failures += reportError(bd, expected, longValue, isInt);
+                    }
+                }
+            } catch (Exception e) {
+                failures++;
+                System.err.format("Unexpected exception %s for %s%n",
+                                  e, bd.toString());
+            }
+        }
+        return failures;
+    }
+
+    private static int reportError(BigDecimal bd, Number expected, long longValue, boolean isInt) {
+        System.err.format("For %s, scale=%d, expected %d, actual %d, simple %d%n",
+                          bd.toString(), bd.scale(),
+                          (isInt ? (Integer) expected : (Long) expected ),
+                          longValue,
+                          (isInt ? simpleIntValue(bd): simpleLongValue(bd) ));
+        return 1;
+    }
+
+    private static long simpleLongValue(BigDecimal bd) {
+        return bd.toBigInteger().longValue();
+    }
+
+    private static int simpleIntValue(BigDecimal bd) {
+        return bd.toBigInteger().intValue();
+    }
+}

test/jdk/java/math/BigDecimal/LongValueExactTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,65 +23,98 @@
 
 /**
  * @test
- * @bug 6806261
+ * @bug 6806261 8211936
  * @summary Tests of BigDecimal.longValueExact
  */
 import java.math.*;
+import java.util.List;
+import java.util.Map;
+import static java.util.Map.entry;
 
 public class LongValueExactTests {
-
+    public static void main(String... args) {
-    private static int longValueExactTests() {
         int failures = 0;
 
-        String[] testStrings = {
+        failures += longValueExactSuccessful();
-            "9223372036854775807",
+        failures += longValueExactExceptional();
-            "9223372036854775807.0",
-            "9223372036854775807.00",
-            "-9223372036854775808",
-            "-9223372036854775808.0",
-            "-9223372036854775808.00",
-        };
-
-        for (String longValue : testStrings) {
-            try {
-                BigDecimal bd = new BigDecimal(longValue);
-                long longValueExact = bd.longValueExact();
-            } catch (Exception e) {
-                failures++;
-            }
-        }
-
-        // The following Strings are supposed to make longValueExact throw
-        // ArithmeticException.
-        String[] testStrings2 = {
-            "9223372036854775808",
-            "9223372036854775808.0",
-            "9223372036854775808.00",
-            "-9223372036854775809",
-            "-9223372036854775808.1",
-            "-9223372036854775808.01",
-        };
-
-        for (String bigValue : testStrings2) {
-            try {
-                BigDecimal bd = new BigDecimal(bigValue);
-                long longValueExact = bd.longValueExact();
-                failures++;
-            } catch (ArithmeticException e) {
-                // Success;
-            }
-        }
-        return failures;
-    }
-
-    public static void main(String argv[]) {
-        int failures = 0;
-
-        failures += longValueExactTests();
 
         if (failures > 0) {
             throw new RuntimeException("Incurred " + failures +
                                        " failures while testing longValueExact.");
         }
     }
+
+    private static long simpleLongValueExact(BigDecimal bd) {
+        return bd.toBigIntegerExact().longValue();
+    }
+
+    private static int longValueExactSuccessful() {
+        int failures = 0;
+
+        // Strings used to create BigDecimal instances on which invoking
+        // longValueExact() will succeed.
+        Map<BigDecimal, Long> successCases =
+            Map.ofEntries(entry(new BigDecimal("9223372036854775807"),    Long.MAX_VALUE), // 2^63 -1
+                          entry(new BigDecimal("9223372036854775807.0"),  Long.MAX_VALUE),
+                          entry(new BigDecimal("9223372036854775807.00"), Long.MAX_VALUE),
+
+                          entry(new BigDecimal("-9223372036854775808"),   Long.MIN_VALUE), // -2^63
+                          entry(new BigDecimal("-9223372036854775808.0"), Long.MIN_VALUE),
+                          entry(new BigDecimal("-9223372036854775808.00"),Long.MIN_VALUE),
+
+                          entry(new BigDecimal("1e0"),    1L),
+                          entry(new BigDecimal(BigInteger.ONE, -18),   1_000_000_000_000_000_000L),
+
+                          entry(new BigDecimal("0e13"),   0L), // Fast path zero
+                          entry(new BigDecimal("0e64"),   0L),
+                          entry(new BigDecimal("0e1024"), 0L),
+
+                          entry(new BigDecimal("10.000000000000000000000000000000000"), 10L));
+
+        for (var testCase : successCases.entrySet()) {
+            BigDecimal bd = testCase.getKey();
+            long expected = testCase.getValue();
+            try {
+                long longValueExact = bd.longValueExact();
+                if (expected != longValueExact ||
+                    longValueExact != simpleLongValueExact(bd)) {
+                    failures++;
+                    System.err.println("Unexpected longValueExact result " + longValueExact +
+                                       " on " + bd);
+                }
+            } catch (Exception e) {
+                failures++;
+                System.err.println("Error on " + bd + "\tException message:" + e.getMessage());
+            }
+        }
+        return failures;
+    }
+
+    private static int longValueExactExceptional() {
+        int failures = 0;
+        List<BigDecimal> exceptionalCases =
+            List.of(new BigDecimal("9223372036854775808"), // Long.MAX_VALUE + 1
+                    new BigDecimal("9223372036854775808.0"),
+                    new BigDecimal("9223372036854775808.00"),
+                    new BigDecimal("-9223372036854775809"), // Long.MIN_VALUE - 1
+                    new BigDecimal("-9223372036854775808.1"),
+                    new BigDecimal("-9223372036854775808.01"),
+
+                    new BigDecimal("9999999999999999999"),
+                    new BigDecimal("10000000000000000000"),
+
+                    new BigDecimal("0.99"),
+                    new BigDecimal("0.999999999999999999999"));
+
+        for (BigDecimal bd : exceptionalCases) {
+            try {
+                long longValueExact = bd.longValueExact();
+                failures++;
+                System.err.println("Unexpected non-exceptional longValueExact on " + bd);
+            } catch (ArithmeticException e) {
+                // Success;
+            }
+        }
+        return failures;
+    }
 }