PrintfRecord.java revision e77b06d21580f630e0a7c437495ab283d3672828
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* ident "%Z%%M% %I% %E% SMI"
*/
package org.opensolaris.os.dtrace;
import java.io.*;
import java.beans.*;
import java.util.*;
/**
* A formatted string generated by the DTrace {@code printf()} action.
* <p>
* Immutable. Supports persistence using {@link java.beans.XMLEncoder}.
*
* @author Tom Erickson
*/
public final class PrintfRecord implements Record, Serializable,
Comparable <PrintfRecord> {
static final long serialVersionUID = 727237355963977675L;
static {
try {
BeanInfo info = Introspector.getBeanInfo(PrintfRecord.class);
PersistenceDelegate persistenceDelegate =
new DefaultPersistenceDelegate(
new String[] {"records", "formattedString"})
{
/*
* Need to prevent DefaultPersistenceDelegate from using
* overridden equals() method, resulting in a
* StackOverFlowError. Revert to PersistenceDelegate
* implementation. See
* http://forum.java.sun.com/thread.jspa?threadID=
* 477019&tstart=135
*/
protected boolean
mutatesTo(Object oldInstance, Object newInstance)
{
return (newInstance != null && oldInstance != null &&
oldInstance.getClass() == newInstance.getClass());
}
};
BeanDescriptor d = info.getBeanDescriptor();
d.setValue("persistenceDelegate", persistenceDelegate);
} catch (IntrospectionException e) {
System.out.println(e);
}
}
/** @serial */
private List <ValueRecord> records;
/** @serial */
private String formattedString;
// package-level access, called by ProbeData
PrintfRecord()
{
records = new ArrayList <ValueRecord> ();
}
/**
* Creates a record with the unformatted elements passed to the
* DTrace {@code printf()} action and the resulting formatted
* output. Supports XML persistence.
*
* @param v variable number of unformatted elements passed to the
* DTrace {@code printf()} action
* @param s formatted {@code printf()} output
* @throws NullPointerException if the given list or any of its
* elements is {@code null}, or if the given formatted string is
* {@code null}
*/
public
PrintfRecord(List <ValueRecord> v, String s)
{
formattedString = s;
records = new ArrayList <ValueRecord> (v.size());
records.addAll(v);
validate();
}
private final void
validate()
{
if (formattedString == null) {
throw new NullPointerException("formatted string is null");
}
if (records == null) {
throw new NullPointerException("list of format args is null");
}
for (ValueRecord r : records) {
if (r == null) {
throw new NullPointerException("format arg is null");
}
}
}
/**
* Called by ProbeData code to populate record list.
*
* @throws NullPointerException if o is null
*/
void
addUnformattedElement(ScalarRecord rec)
{
records.add(rec);
}
/**
* Gets the formatted string output of the DTrace {@code printf()}
* action.
*
* @return non-null formatted string output of the DTrace {@code
* printf()} action
*/
public String
getFormattedString()
{
return formattedString;
}
/**
* Package level access; called by ProbeData
*/
void
setFormattedString(String s)
{
if (s == null) {
throw new NullPointerException("formatted string is null");
}
formattedString = s;
}
/**
* Gets the unfomatted elements passed to the DTrace {@code
* printf()} action after the format string.
*
* @return non-null, unmodifiable list of unformatted elements
* passed to the DTrace {@code printf()} action that generated this
* record, in the order they appear in the argument list after the
* format string
*/
public List <ValueRecord>
getRecords()
{
return Collections. <ValueRecord> unmodifiableList(records);
}
/**
* Gets the number of DTrace {@code printf()} unformatted elements
* (arguments following the format string). For example, the
* following action
* <pre><code>
* printf("%s %d\n", "cat", 9);
* </code></pre>
* generates a {@code PrintfRecord} with a record count of two.
*
* @return the number of unformatted elements passed to the DTrace
* {@code printf()} action that generated this record.
*/
public int
getRecordCount()
{
return records.size();
}
/**
* Gets the unformatted element passed to the DTrace {@code
* printf()} action at the given offset in the {@code printf()}
* argument list after the format string, starting at offset zero
* for the first unformatted element.
*
* @return non-null record representing the unformatted {@code
* printf()} element at the given index (using the same order that
* they appear in the {@code printf()} argument list)
* @throws ArrayIndexOutOfBoundsException if the given index is
* out of range (index < 0 || index >= getRecordCount())
*/
public ValueRecord
getRecord(int i)
{
return records.get(i);
}
/**
* Compares the specified object with this {@code PrintfRecord} for
* equality. Returns {@code true} if and only if the specified
* object is also a {@code PrintfRecord} and both records have the
* same formatted string and underlying data elements.
*
* @return {@code true} if and only if the specified object is also
* a {@code PrintfRecord} and both the formatted strings <i>and</i>
* the underlying data elements of both records are equal
*/
@Override
public boolean
equals(Object o)
{
if (o instanceof PrintfRecord) {
PrintfRecord r = (PrintfRecord)o;
return (records.equals(r.records) &&
formattedString.equals(r.formattedString));
}
return false;
}
/**
* Overridden to ensure that equal instances have equal hash codes.
*/
@Override
public int
hashCode()
{
int hash = 17;
hash = (37 * hash) + records.hashCode();
hash = (37 * hash) + formattedString.hashCode();
return hash;
}
/**
* Compares the formatted string value of this record with that of
* the given record. Note that ordering {@code printf} records by
* their string values is incompatible with {@link #equals(Object o)
* equals()}, which also checks the underlying data elements for
* equality.
*
* @return a negative number, 0, or a positive number as this
* record's formatted string is lexicographically less than, equal
* to, or greater than the given record's formatted string
*/
public int
compareTo(PrintfRecord r)
{
return formattedString.compareTo(r.formattedString);
}
private void
readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException
{
s.defaultReadObject();
// Defensively copy record list before validating
if (records == null) {
throw new InvalidObjectException("record list is null");
}
List <ValueRecord> copy = new ArrayList <ValueRecord> (records.size());
copy.addAll(records);
records = copy;
// check invariants
try {
validate();
} catch (Exception e) {
InvalidObjectException x = new InvalidObjectException(
e.getMessage());
x.initCause(e);
throw x;
}
}
/**
* Gets the formatted string output of the DTrace {@code printf()}
* action.
*/
public String
toString()
{
return formattedString;
}
}