6253144: Long narrowing conversion should describe the algorithm used and implied "risks"
Reviewed-by: mduigou, alanb
--- a/jdk/src/share/classes/java/lang/Byte.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Byte.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1996, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2011, 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
@@ -324,40 +324,45 @@
}
/**
- * Returns the value of this {@code Byte} as a
- * {@code short}.
+ * Returns the value of this {@code Byte} as a {@code short} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public short shortValue() {
return (short)value;
}
/**
- * Returns the value of this {@code Byte} as an
- * {@code int}.
+ * Returns the value of this {@code Byte} as an {@code int} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public int intValue() {
return (int)value;
}
/**
- * Returns the value of this {@code Byte} as a
- * {@code long}.
+ * Returns the value of this {@code Byte} as a {@code long} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public long longValue() {
return (long)value;
}
/**
- * Returns the value of this {@code Byte} as a
- * {@code float}.
+ * Returns the value of this {@code Byte} as a {@code float} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public float floatValue() {
return (float)value;
}
/**
- * Returns the value of this {@code Byte} as a
- * {@code double}.
+ * Returns the value of this {@code Byte} as a {@code double}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public double doubleValue() {
return (double)value;
--- a/jdk/src/share/classes/java/lang/Double.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Double.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2011, 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
@@ -634,11 +634,12 @@
}
/**
- * Returns the value of this {@code Double} as a {@code byte} (by
- * casting to a {@code byte}).
+ * Returns the value of this {@code Double} as a {@code byte}
+ * after a narrowing primitive conversion.
*
* @return the {@code double} value represented by this object
* converted to type {@code byte}
+ * @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.1
*/
public byte byteValue() {
@@ -646,11 +647,12 @@
}
/**
- * Returns the value of this {@code Double} as a
- * {@code short} (by casting to a {@code short}).
+ * Returns the value of this {@code Double} as a {@code short}
+ * after a narrowing primitive conversion.
*
* @return the {@code double} value represented by this object
* converted to type {@code short}
+ * @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.1
*/
public short shortValue() {
@@ -658,8 +660,9 @@
}
/**
- * Returns the value of this {@code Double} as an
- * {@code int} (by casting to type {@code int}).
+ * Returns the value of this {@code Double} as an {@code int}
+ * after a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*
* @return the {@code double} value represented by this object
* converted to type {@code int}
@@ -669,22 +672,24 @@
}
/**
- * Returns the value of this {@code Double} as a
- * {@code long} (by casting to type {@code long}).
+ * Returns the value of this {@code Double} as a {@code long}
+ * after a narrowing primitive conversion.
*
* @return the {@code double} value represented by this object
* converted to type {@code long}
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public long longValue() {
return (long)value;
}
/**
- * Returns the {@code float} value of this
- * {@code Double} object.
+ * Returns the value of this {@code Double} as a {@code float}
+ * after a narrowing primitive conversion.
*
* @return the {@code double} value represented by this object
* converted to type {@code float}
+ * @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.0
*/
public float floatValue() {
@@ -692,8 +697,7 @@
}
/**
- * Returns the {@code double} value of this
- * {@code Double} object.
+ * Returns the {@code double} value of this {@code Double} object.
*
* @return the {@code double} value represented by this object
*/
--- a/jdk/src/share/classes/java/lang/Float.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Float.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2011, 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
@@ -556,22 +556,24 @@
}
/**
- * Returns the value of this {@code Float} as a {@code byte} (by
- * casting to a {@code byte}).
+ * Returns the value of this {@code Float} as a {@code byte} after
+ * a narrowing primitive conversion.
*
* @return the {@code float} value represented by this object
* converted to type {@code byte}
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public byte byteValue() {
return (byte)value;
}
/**
- * Returns the value of this {@code Float} as a {@code short} (by
- * casting to a {@code short}).
+ * Returns the value of this {@code Float} as a {@code short}
+ * after a narrowing primitive conversion.
*
* @return the {@code float} value represented by this object
* converted to type {@code short}
+ * @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.1
*/
public short shortValue() {
@@ -579,22 +581,24 @@
}
/**
- * Returns the value of this {@code Float} as an {@code int} (by
- * casting to type {@code int}).
+ * Returns the value of this {@code Float} as an {@code int} after
+ * a narrowing primitive conversion.
*
* @return the {@code float} value represented by this object
* converted to type {@code int}
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public int intValue() {
return (int)value;
}
/**
- * Returns value of this {@code Float} as a {@code long} (by
- * casting to type {@code long}).
+ * Returns value of this {@code Float} as a {@code long} after a
+ * narrowing primitive conversion.
*
* @return the {@code float} value represented by this object
* converted to type {@code long}
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public long longValue() {
return (long)value;
@@ -610,11 +614,12 @@
}
/**
- * Returns the {@code double} value of this {@code Float} object.
+ * Returns the value of this {@code Float} as a {@code double}
+ * after a widening primitive conversion.
*
* @return the {@code float} value represented by this
- * object is converted to type {@code double} and the
- * result of the conversion is returned.
+ * object converted to type {@code double}
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public double doubleValue() {
return (double)value;
--- a/jdk/src/share/classes/java/lang/Integer.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Integer.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2011, 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
@@ -678,16 +678,18 @@
}
/**
- * Returns the value of this {@code Integer} as a
- * {@code byte}.
+ * Returns the value of this {@code Integer} as a {@code byte}
+ * after a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public byte byteValue() {
return (byte)value;
}
/**
- * Returns the value of this {@code Integer} as a
- * {@code short}.
+ * Returns the value of this {@code Integer} as a {@code short}
+ * after a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public short shortValue() {
return (short)value;
@@ -702,24 +704,27 @@
}
/**
- * Returns the value of this {@code Integer} as a
- * {@code long}.
+ * Returns the value of this {@code Integer} as a {@code long}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public long longValue() {
return (long)value;
}
/**
- * Returns the value of this {@code Integer} as a
- * {@code float}.
+ * Returns the value of this {@code Integer} as a {@code float}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public float floatValue() {
return (float)value;
}
/**
- * Returns the value of this {@code Integer} as a
- * {@code double}.
+ * Returns the value of this {@code Integer} as a {@code double}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public double doubleValue() {
return (double)value;
--- a/jdk/src/share/classes/java/lang/Long.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Long.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1994, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2011, 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
@@ -703,24 +703,27 @@
}
/**
- * Returns the value of this {@code Long} as a
- * {@code byte}.
+ * Returns the value of this {@code Long} as a {@code byte} after
+ * a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public byte byteValue() {
return (byte)value;
}
/**
- * Returns the value of this {@code Long} as a
- * {@code short}.
+ * Returns the value of this {@code Long} as a {@code short} after
+ * a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public short shortValue() {
return (short)value;
}
/**
- * Returns the value of this {@code Long} as an
- * {@code int}.
+ * Returns the value of this {@code Long} as an {@code int} after
+ * a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public int intValue() {
return (int)value;
@@ -735,16 +738,18 @@
}
/**
- * Returns the value of this {@code Long} as a
- * {@code float}.
+ * Returns the value of this {@code Long} as a {@code float} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public float floatValue() {
return (float)value;
}
/**
- * Returns the value of this {@code Long} as a
- * {@code double}.
+ * Returns the value of this {@code Long} as a {@code double}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public double doubleValue() {
return (double)value;
--- a/jdk/src/share/classes/java/lang/Number.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Number.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1994, 2001, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2011, 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
@@ -26,69 +26,78 @@
package java.lang;
/**
- * The abstract class <code>Number</code> is the superclass of classes
- * <code>BigDecimal</code>, <code>BigInteger</code>,
- * <code>Byte</code>, <code>Double</code>, <code>Float</code>,
- * <code>Integer</code>, <code>Long</code>, and <code>Short</code>.
- * <p>
- * Subclasses of <code>Number</code> must provide methods to convert
- * the represented numeric value to <code>byte</code>, <code>double</code>,
- * <code>float</code>, <code>int</code>, <code>long</code>, and
- * <code>short</code>.
+ * The abstract class {@code Number} is the superclass of platform
+ * classes representing numeric values that are convertible to the
+ * primitive types {@code byte}, {@code double}, {@code float}, {@code
+ * int}, {@code long}, and {@code short}.
+ *
+ * The specific semantics of the conversion from the numeric value of
+ * a particular {@code Number} implementation to a given primitive
+ * type is defined by the {@code Number} implementation in question.
+ *
+ * For platform classes, the conversion is often analogous to a
+ * narrowing primitive conversion or a widening primitive conversion
+ * as defining in <cite>The Java™ Language Specification</cite>
+ * for converting between primitive types. Therefore, conversions may
+ * lose information about the overall magnitude of a numeric value, may
+ * lose precision, and may even return a result of a different sign
+ * than the input.
+ *
+ * See the documentation of a given {@code Number} implementation for
+ * conversion details.
*
* @author Lee Boynton
* @author Arthur van Hoff
- * @see java.lang.Byte
- * @see java.lang.Double
- * @see java.lang.Float
- * @see java.lang.Integer
- * @see java.lang.Long
- * @see java.lang.Short
+ * @jls 5.1.2 Widening Primitive Conversions
+ * @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.0
*/
public abstract class Number implements java.io.Serializable {
/**
- * Returns the value of the specified number as an <code>int</code>.
- * This may involve rounding or truncation.
+ * Returns the value of the specified number as an {@code int},
+ * which may involve rounding or truncation.
*
* @return the numeric value represented by this object after conversion
- * to type <code>int</code>.
+ * to type {@code int}.
*/
public abstract int intValue();
/**
- * Returns the value of the specified number as a <code>long</code>.
- * This may involve rounding or truncation.
+ * Returns the value of the specified number as a {@code long},
+ * which may involve rounding or truncation.
*
* @return the numeric value represented by this object after conversion
- * to type <code>long</code>.
+ * to type {@code long}.
*/
public abstract long longValue();
/**
- * Returns the value of the specified number as a <code>float</code>.
- * This may involve rounding.
+ * Returns the value of the specified number as a {@code float},
+ * which may involve rounding.
*
* @return the numeric value represented by this object after conversion
- * to type <code>float</code>.
+ * to type {@code float}.
*/
public abstract float floatValue();
/**
- * Returns the value of the specified number as a <code>double</code>.
- * This may involve rounding.
+ * Returns the value of the specified number as a {@code double},
+ * which may involve rounding.
*
* @return the numeric value represented by this object after conversion
- * to type <code>double</code>.
+ * to type {@code double}.
*/
public abstract double doubleValue();
/**
- * Returns the value of the specified number as a <code>byte</code>.
- * This may involve rounding or truncation.
+ * Returns the value of the specified number as a {@code byte},
+ * which may involve rounding or truncation.
+ *
+ * <p>This implementation returns the result of {@link #intValue} cast
+ * to a {@code byte}.
*
* @return the numeric value represented by this object after conversion
- * to type <code>byte</code>.
+ * to type {@code byte}.
* @since JDK1.1
*/
public byte byteValue() {
@@ -96,11 +105,14 @@
}
/**
- * Returns the value of the specified number as a <code>short</code>.
- * This may involve rounding or truncation.
+ * Returns the value of the specified number as a {@code short},
+ * which may involve rounding or truncation.
+ *
+ * <p>This implementation returns the result of {@link #intValue} cast
+ * to a {@code short}.
*
* @return the numeric value represented by this object after conversion
- * to type <code>short</code>.
+ * to type {@code short}.
* @since JDK1.1
*/
public short shortValue() {
--- a/jdk/src/share/classes/java/lang/Short.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/lang/Short.java Thu Jun 23 14:57:57 2011 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1996, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2011, 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
@@ -321,8 +321,9 @@
}
/**
- * Returns the value of this {@code Short} as a
- * {@code byte}.
+ * Returns the value of this {@code Short} as a {@code byte} after
+ * a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
*/
public byte byteValue() {
return (byte)value;
@@ -337,32 +338,36 @@
}
/**
- * Returns the value of this {@code Short} as an
- * {@code int}.
+ * Returns the value of this {@code Short} as an {@code int} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public int intValue() {
return (int)value;
}
/**
- * Returns the value of this {@code Short} as a
- * {@code long}.
+ * Returns the value of this {@code Short} as a {@code long} after
+ * a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public long longValue() {
return (long)value;
}
/**
- * Returns the value of this {@code Short} as a
- * {@code float}.
+ * Returns the value of this {@code Short} as a {@code float}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public float floatValue() {
return (float)value;
}
/**
- * Returns the value of this {@code Short} as a
- * {@code double}.
+ * Returns the value of this {@code Short} as a {@code double}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
*/
public double doubleValue() {
return (double)value;
--- a/jdk/src/share/classes/java/util/concurrent/atomic/AtomicInteger.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/util/concurrent/atomic/AtomicInteger.java Thu Jun 23 14:57:57 2011 -0700
@@ -246,18 +246,37 @@
}
+ /**
+ * Returns the value of this {@code AtomicInteger} as an
+ * {@code int}.
+ */
public int intValue() {
return get();
}
+ /**
+ * Returns the value of this {@code AtomicInteger} as a {@code long}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
+ */
public long longValue() {
return (long)get();
}
+ /**
+ * Returns the value of this {@code AtomicInteger} as a {@code float}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
+ */
public float floatValue() {
return (float)get();
}
+ /**
+ * Returns the value of this {@code AtomicInteger} as a {@code double}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
+ */
public double doubleValue() {
return (double)get();
}
--- a/jdk/src/share/classes/java/util/concurrent/atomic/AtomicLong.java Thu Jun 23 04:23:50 2011 -0700
+++ b/jdk/src/share/classes/java/util/concurrent/atomic/AtomicLong.java Thu Jun 23 14:57:57 2011 -0700
@@ -260,18 +260,37 @@
}
+ /**
+ * Returns the value of this {@code AtomicLong} as an {@code int}
+ * after a narrowing primitive conversion.
+ * @jls 5.1.3 Narrowing Primitive Conversions
+ */
public int intValue() {
return (int)get();
}
+ /**
+ * Returns the value of this {@code AtomicLong} as a {@code long}
+ * value.
+ */
public long longValue() {
return get();
}
+ /**
+ * Returns the value of this {@code AtomicLong} as a {@code float}
+ * after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
+ */
public float floatValue() {
return (float)get();
}
+ /**
+ * Returns the value of this {@code AtomicLong} as a {@code
+ * double} after a widening primitive conversion.
+ * @jls 5.1.2 Widening Primitive Conversions
+ */
public double doubleValue() {
return (double)get();
}