src/java.base/share/classes/java/lang/Long.java
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@@ -28,10 +28,13 @@
import java.lang.annotation.Native;
import java.math.*;
import java.util.Objects;
import jdk.internal.HotSpotIntrinsicCandidate;
+import static java.lang.String.COMPACT_STRINGS;
+import static java.lang.String.LATIN1;
+import static java.lang.String.UTF16;
/**
* The {@code Long} class wraps a value of the primitive type {@code
* long} in an object. An object of type {@code Long} contains a
* single field whose type is {@code long}.
@@ -122,29 +125,50 @@
public static String toString(long i, int radix) {
if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
radix = 10;
if (radix == 10)
return toString(i);
- char[] buf = new char[65];
+
+ if (COMPACT_STRINGS) {
+ byte[] buf = new byte[65];
int charPos = 64;
boolean negative = (i < 0);
if (!negative) {
i = -i;
}
while (i <= -radix) {
- buf[charPos--] = Integer.digits[(int)(-(i % radix))];
+ buf[charPos--] = (byte)Integer.digits[(int)(-(i % radix))];
i = i / radix;
}
- buf[charPos] = Integer.digits[(int)(-i)];
+ buf[charPos] = (byte)Integer.digits[(int)(-i)];
if (negative) {
buf[--charPos] = '-';
}
+ return StringLatin1.newString(buf, charPos, (65 - charPos));
+ }
+ return toStringUTF16(i, radix);
+ }
- return new String(buf, charPos, (65 - charPos));
+ private static String toStringUTF16(long i, int radix) {
+ byte[] buf = new byte[65 * 2];
+ int charPos = 64;
+ boolean negative = (i < 0);
+ if (!negative) {
+ i = -i;
+ }
+ while (i <= -radix) {
+ StringUTF16.putChar(buf, charPos--, Integer.digits[(int)(-(i % radix))]);
+ i = i / radix;
+ }
+ StringUTF16.putChar(buf, charPos, Integer.digits[(int)(-i)]);
+ if (negative) {
+ StringUTF16.putChar(buf, --charPos, '-');
+ }
+ return StringUTF16.newString(buf, charPos, (65 - charPos));
}
/**
* Returns a string representation of the first argument as an
* unsigned integer value in the radix specified by the second
@@ -353,14 +377,20 @@
*/
static String toUnsignedString0(long val, int shift) {
// assert shift > 0 && shift <=5 : "Illegal shift value";
int mag = Long.SIZE - Long.numberOfLeadingZeros(val);
int chars = Math.max(((mag + (shift - 1)) / shift), 1);
- char[] buf = new char[chars];
- formatUnsignedLong(val, shift, buf, 0, chars);
- return new String(buf, true);
+ if (COMPACT_STRINGS) {
+ byte[] buf = new byte[chars];
+ formatUnsignedLong0(val, shift, buf, 0, chars);
+ return new String(buf, LATIN1);
+ } else {
+ byte[] buf = new byte[chars * 2];
+ formatUnsignedLong0UTF16(val, shift, buf, 0, chars);
+ return new String(buf, UTF16);
+ }
}
/**
* Format a long (treated as unsigned) into a character buffer. If
* {@code len} exceeds the formatted ASCII representation of {@code val},
@@ -383,10 +413,32 @@
buf[--charPos] = Integer.digits[((int) val) & mask];
val >>>= shift;
} while (charPos > offset);
}
+ /** byte[]/LATIN1 version */
+ static void formatUnsignedLong0(long val, int shift, byte[] buf, int offset, int len) {
+ int charPos = offset + len;
+ int radix = 1 << shift;
+ int mask = radix - 1;
+ do {
+ buf[--charPos] = (byte)Integer.digits[((int) val) & mask];
+ val >>>= shift;
+ } while (charPos > offset);
+ }
+
+ /** byte[]/UTF16 version */
+ static void formatUnsignedLong0UTF16(long val, int shift, byte[] buf, int offset, int len) {
+ int charPos = offset + len;
+ int radix = 1 << shift;
+ int mask = radix - 1;
+ do {
+ StringUTF16.putChar(buf, --charPos, Integer.digits[((int) val) & mask]);
+ val >>>= shift;
+ } while (charPos > offset);
+ }
+
/**
* Returns a {@code String} object representing the specified
* {@code long}. The argument is converted to signed decimal
* representation and returned as a string, exactly as if the
* argument and the radix 10 were given as arguments to the {@link
@@ -397,13 +449,19 @@
*/
public static String toString(long i) {
if (i == Long.MIN_VALUE)
return "-9223372036854775808";
int size = (i < 0) ? stringSize(-i) + 1 : stringSize(i);
- char[] buf = new char[size];
+ if (COMPACT_STRINGS) {
+ byte[] buf = new byte[size];
getChars(i, size, buf);
- return new String(buf, true);
+ return new String(buf, LATIN1);
+ } else {
+ byte[] buf = new byte[size * 2];
+ getCharsUTF16(i, size, buf);
+ return new String(buf, UTF16);
+ }
}
/**
* Returns a string representation of the argument as an unsigned
* decimal value.
@@ -429,11 +487,58 @@
* digit at the specified index (exclusive), and working
* backwards from there.
*
* Will fail if i == Long.MIN_VALUE
*/
- static void getChars(long i, int index, char[] buf) {
+ static void getChars(long i, int index, byte[] buf) {
+ long q;
+ int r;
+ int charPos = index;
+ char sign = 0;
+
+ if (i < 0) {
+ sign = '-';
+ i = -i;
+ }
+
+ // Get 2 digits/iteration using longs until quotient fits into an int
+ while (i > Integer.MAX_VALUE) {
+ q = i / 100;
+ // really: r = i - (q * 100);
+ r = (int)(i - ((q << 6) + (q << 5) + (q << 2)));
+ i = q;
+ buf[--charPos] = (byte)Integer.DigitOnes[r];
+ buf[--charPos] = (byte)Integer.DigitTens[r];
+ }
+
+ // Get 2 digits/iteration using ints
+ int q2;
+ int i2 = (int)i;
+ while (i2 >= 65536) {
+ q2 = i2 / 100;
+ // really: r = i2 - (q * 100);
+ r = i2 - ((q2 << 6) + (q2 << 5) + (q2 << 2));
+ i2 = q2;
+ buf[--charPos] = (byte)Integer.DigitOnes[r];
+ buf[--charPos] = (byte)Integer.DigitTens[r];
+ }
+
+ // Fall thru to fast mode for smaller numbers
+ // assert(i2 <= 65536, i2);
+ for (;;) {
+ q2 = (i2 * 52429) >>> (16+3);
+ r = i2 - ((q2 << 3) + (q2 << 1)); // r = i2-(q2*10) ...
+ buf[--charPos] = (byte)Integer.digits[r];
+ i2 = q2;
+ if (i2 == 0) break;
+ }
+ if (sign != 0) {
+ buf[--charPos] = (byte)sign;
+ }
+ }
+
+ static void getCharsUTF16(long i, int index, byte[] buf) {
long q;
int r;
int charPos = index;
char sign = 0;
@@ -446,37 +551,37 @@
while (i > Integer.MAX_VALUE) {
q = i / 100;
// really: r = i - (q * 100);
r = (int)(i - ((q << 6) + (q << 5) + (q << 2)));
i = q;
- buf[--charPos] = Integer.DigitOnes[r];
- buf[--charPos] = Integer.DigitTens[r];
+ StringUTF16.putChar(buf, --charPos, Integer.DigitOnes[r]);
+ StringUTF16.putChar(buf, --charPos, Integer.DigitTens[r]);
}
// Get 2 digits/iteration using ints
int q2;
int i2 = (int)i;
while (i2 >= 65536) {
q2 = i2 / 100;
// really: r = i2 - (q * 100);
r = i2 - ((q2 << 6) + (q2 << 5) + (q2 << 2));
i2 = q2;
- buf[--charPos] = Integer.DigitOnes[r];
- buf[--charPos] = Integer.DigitTens[r];
+ StringUTF16.putChar(buf, --charPos, Integer.DigitOnes[r]);
+ StringUTF16.putChar(buf, --charPos, Integer.DigitTens[r]);
}
// Fall thru to fast mode for smaller numbers
// assert(i2 <= 65536, i2);
for (;;) {
q2 = (i2 * 52429) >>> (16+3);
r = i2 - ((q2 << 3) + (q2 << 1)); // r = i2-(q2*10) ...
- buf[--charPos] = Integer.digits[r];
+ StringUTF16.putChar(buf, --charPos, Integer.digits[r]);
i2 = q2;
if (i2 == 0) break;
}
if (sign != 0) {
- buf[--charPos] = sign;
+ StringUTF16.putChar(buf, --charPos, sign);
}
}
// Requires positive x
static int stringSize(long x) {