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src/java.management/share/classes/java/lang/management/MemoryUsage.java
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*** 27,80 ****
import javax.management.openmbean.CompositeData;
import sun.management.MemoryUsageCompositeData;
/**
! * A <tt>MemoryUsage</tt> object represents a snapshot of memory usage.
! * Instances of the <tt>MemoryUsage</tt> class are usually constructed
* by methods that are used to obtain memory usage
* information about individual memory pool of the Java virtual machine or
* the heap or non-heap memory of the Java virtual machine as a whole.
*
! * <p> A <tt>MemoryUsage</tt> object contains four values:
* <table summary="Describes the MemoryUsage object content">
* <tr>
! * <td valign=top> <tt>init</tt> </td>
* <td valign=top> represents the initial amount of memory (in bytes) that
* the Java virtual machine requests from the operating system
* for memory management during startup. The Java virtual machine
* may request additional memory from the operating system and
* may also release memory to the system over time.
! * The value of <tt>init</tt> may be undefined.
* </td>
* </tr>
* <tr>
! * <td valign=top> <tt>used</tt> </td>
* <td valign=top> represents the amount of memory currently used (in bytes).
* </td>
* </tr>
* <tr>
! * <td valign=top> <tt>committed</tt> </td>
* <td valign=top> represents the amount of memory (in bytes) that is
* guaranteed to be available for use by the Java virtual machine.
* The amount of committed memory may change over time (increase
* or decrease). The Java virtual machine may release memory to
! * the system and <tt>committed</tt> could be less than <tt>init</tt>.
! * <tt>committed</tt> will always be greater than
! * or equal to <tt>used</tt>.
* </td>
* </tr>
* <tr>
! * <td valign=top> <tt>max</tt> </td>
* <td valign=top> represents the maximum amount of memory (in bytes)
* that can be used for memory management. Its value may be undefined.
* The maximum amount of memory may change over time if defined.
* The amount of used and committed memory will always be less than
! * or equal to <tt>max</tt> if <tt>max</tt> is defined.
* A memory allocation may fail if it attempts to increase the
! * used memory such that <tt>used > committed</tt> even
! * if <tt>used <= max</tt> would still be true (for example,
* when the system is low on virtual memory).
* </td>
* </tr>
* </table>
*
--- 27,80 ----
import javax.management.openmbean.CompositeData;
import sun.management.MemoryUsageCompositeData;
/**
! * A {@code MemoryUsage} object represents a snapshot of memory usage.
! * Instances of the {@code MemoryUsage} class are usually constructed
* by methods that are used to obtain memory usage
* information about individual memory pool of the Java virtual machine or
* the heap or non-heap memory of the Java virtual machine as a whole.
*
! * <p> A {@code MemoryUsage} object contains four values:
* <table summary="Describes the MemoryUsage object content">
* <tr>
! * <td valign=top> {@code init} </td>
* <td valign=top> represents the initial amount of memory (in bytes) that
* the Java virtual machine requests from the operating system
* for memory management during startup. The Java virtual machine
* may request additional memory from the operating system and
* may also release memory to the system over time.
! * The value of {@code init} may be undefined.
* </td>
* </tr>
* <tr>
! * <td valign=top> {@code used} </td>
* <td valign=top> represents the amount of memory currently used (in bytes).
* </td>
* </tr>
* <tr>
! * <td valign=top> {@code committed} </td>
* <td valign=top> represents the amount of memory (in bytes) that is
* guaranteed to be available for use by the Java virtual machine.
* The amount of committed memory may change over time (increase
* or decrease). The Java virtual machine may release memory to
! * the system and {@code committed} could be less than {@code init}.
! * {@code committed} will always be greater than
! * or equal to {@code used}.
* </td>
* </tr>
* <tr>
! * <td valign=top> {@code max} </td>
* <td valign=top> represents the maximum amount of memory (in bytes)
* that can be used for memory management. Its value may be undefined.
* The maximum amount of memory may change over time if defined.
* The amount of used and committed memory will always be less than
! * or equal to {@code max} if {@code max} is defined.
* A memory allocation may fail if it attempts to increase the
! * used memory such that {@code used > committed} even
! * if {@code used <= max} would still be true (for example,
* when the system is low on virtual memory).
* </td>
* </tr>
* </table>
*
*** 95,105 ****
* |----------------------------------------------|
* max
* </pre>
*
* <h3>MXBean Mapping</h3>
! * <tt>MemoryUsage</tt> is mapped to a {@link CompositeData CompositeData}
* with attributes as specified in the {@link #from from} method.
*
* @author Mandy Chung
* @since 1.5
*/
--- 95,105 ----
* |----------------------------------------------|
* max
* </pre>
*
* <h3>MXBean Mapping</h3>
! * {@code MemoryUsage} is mapped to a {@link CompositeData CompositeData}
* with attributes as specified in the {@link #from from} method.
*
* @author Mandy Chung
* @since 1.5
*/
*** 108,137 ****
private final long used;
private final long committed;
private final long max;
/**
! * Constructs a <tt>MemoryUsage</tt> object.
*
* @param init the initial amount of memory in bytes that
* the Java virtual machine allocates;
! * or <tt>-1</tt> if undefined.
* @param used the amount of used memory in bytes.
* @param committed the amount of committed memory in bytes.
* @param max the maximum amount of memory in bytes that
! * can be used; or <tt>-1</tt> if undefined.
*
* @throws IllegalArgumentException if
* <ul>
! * <li> the value of <tt>init</tt> or <tt>max</tt> is negative
! * but not <tt>-1</tt>; or</li>
! * <li> the value of <tt>used</tt> or <tt>committed</tt> is negative;
* or</li>
! * <li> <tt>used</tt> is greater than the value of <tt>committed</tt>;
* or</li>
! * <li> <tt>committed</tt> is greater than the value of <tt>max</tt>
! * <tt>max</tt> if defined.</li>
* </ul>
*/
public MemoryUsage(long init,
long used,
long committed,
--- 108,137 ----
private final long used;
private final long committed;
private final long max;
/**
! * Constructs a {@code MemoryUsage} object.
*
* @param init the initial amount of memory in bytes that
* the Java virtual machine allocates;
! * or {@code -1} if undefined.
* @param used the amount of used memory in bytes.
* @param committed the amount of committed memory in bytes.
* @param max the maximum amount of memory in bytes that
! * can be used; or {@code -1} if undefined.
*
* @throws IllegalArgumentException if
* <ul>
! * <li> the value of {@code init} or {@code max} is negative
! * but not {@code -1}; or</li>
! * <li> the value of {@code used} or {@code committed} is negative;
* or</li>
! * <li> {@code used} is greater than the value of {@code committed};
* or</li>
! * <li> {@code committed} is greater than the value of {@code max}
! * {@code max} if defined.</li>
* </ul>
*/
public MemoryUsage(long init,
long used,
long committed,
*** 166,176 ****
this.committed = committed;
this.max = max;
}
/**
! * Constructs a <tt>MemoryUsage</tt> object from a
* {@link CompositeData CompositeData}.
*/
private MemoryUsage(CompositeData cd) {
// validate the input composite data
MemoryUsageCompositeData.validateCompositeData(cd);
--- 166,176 ----
this.committed = committed;
this.max = max;
}
/**
! * Constructs a {@code MemoryUsage} object from a
* {@link CompositeData CompositeData}.
*/
private MemoryUsage(CompositeData cd) {
// validate the input composite data
MemoryUsageCompositeData.validateCompositeData(cd);
*** 182,195 ****
}
/**
* Returns the amount of memory in bytes that the Java virtual machine
* initially requests from the operating system for memory management.
! * This method returns <tt>-1</tt> if the initial memory size is undefined.
*
* @return the initial size of memory in bytes;
! * <tt>-1</tt> if undefined.
*/
public long getInit() {
return init;
}
--- 182,195 ----
}
/**
* Returns the amount of memory in bytes that the Java virtual machine
* initially requests from the operating system for memory management.
! * This method returns {@code -1} if the initial memory size is undefined.
*
* @return the initial size of memory in bytes;
! * {@code -1} if undefined.
*/
public long getInit() {
return init;
}
*** 215,235 ****
return committed;
};
/**
* Returns the maximum amount of memory in bytes that can be
! * used for memory management. This method returns <tt>-1</tt>
* if the maximum memory size is undefined.
*
* <p> This amount of memory is not guaranteed to be available
* for memory management if it is greater than the amount of
* committed memory. The Java virtual machine may fail to allocate
* memory even if the amount of used memory does not exceed this
* maximum size.
*
* @return the maximum amount of memory in bytes;
! * <tt>-1</tt> if undefined.
*/
public long getMax() {
return max;
};
--- 215,235 ----
return committed;
};
/**
* Returns the maximum amount of memory in bytes that can be
! * used for memory management. This method returns {@code -1}
* if the maximum memory size is undefined.
*
* <p> This amount of memory is not guaranteed to be available
* for memory management if it is greater than the amount of
* committed memory. The Java virtual machine may fail to allocate
* memory even if the amount of used memory does not exceed this
* maximum size.
*
* @return the maximum amount of memory in bytes;
! * {@code -1} if undefined.
*/
public long getMax() {
return max;
};
*** 245,292 ****
buf.append("max = " + max + "(" + (max >> 10) + "K)");
return buf.toString();
}
/**
! * Returns a <tt>MemoryUsage</tt> object represented by the
! * given <tt>CompositeData</tt>. The given <tt>CompositeData</tt>
* must contain the following attributes:
*
* <blockquote>
* <table border summary="The attributes and the types the given CompositeData contains">
* <tr>
* <th align=left>Attribute Name</th>
* <th align=left>Type</th>
* </tr>
* <tr>
* <td>init</td>
! * <td><tt>java.lang.Long</tt></td>
* </tr>
* <tr>
* <td>used</td>
! * <td><tt>java.lang.Long</tt></td>
* </tr>
* <tr>
* <td>committed</td>
! * <td><tt>java.lang.Long</tt></td>
* </tr>
* <tr>
* <td>max</td>
! * <td><tt>java.lang.Long</tt></td>
* </tr>
* </table>
* </blockquote>
*
! * @param cd <tt>CompositeData</tt> representing a <tt>MemoryUsage</tt>
*
! * @throws IllegalArgumentException if <tt>cd</tt> does not
! * represent a <tt>MemoryUsage</tt> with the attributes described
* above.
*
! * @return a <tt>MemoryUsage</tt> object represented by <tt>cd</tt>
! * if <tt>cd</tt> is not <tt>null</tt>;
! * <tt>null</tt> otherwise.
*/
public static MemoryUsage from(CompositeData cd) {
if (cd == null) {
return null;
}
--- 245,292 ----
buf.append("max = " + max + "(" + (max >> 10) + "K)");
return buf.toString();
}
/**
! * Returns a {@code MemoryUsage} object represented by the
! * given {@code CompositeData}. The given {@code CompositeData}
* must contain the following attributes:
*
* <blockquote>
* <table border summary="The attributes and the types the given CompositeData contains">
* <tr>
* <th align=left>Attribute Name</th>
* <th align=left>Type</th>
* </tr>
* <tr>
* <td>init</td>
! * <td>{@code java.lang.Long}</td>
* </tr>
* <tr>
* <td>used</td>
! * <td>{@code java.lang.Long}</td>
* </tr>
* <tr>
* <td>committed</td>
! * <td>{@code java.lang.Long}</td>
* </tr>
* <tr>
* <td>max</td>
! * <td>{@code java.lang.Long}</td>
* </tr>
* </table>
* </blockquote>
*
! * @param cd {@code CompositeData} representing a {@code MemoryUsage}
*
! * @throws IllegalArgumentException if {@code cd} does not
! * represent a {@code MemoryUsage} with the attributes described
* above.
*
! * @return a {@code MemoryUsage} object represented by {@code cd}
! * if {@code cd} is not {@code null};
! * {@code null} otherwise.
*/
public static MemoryUsage from(CompositeData cd) {
if (cd == null) {
return null;
}
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