JDK8/Java8源码在线阅读
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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.
*
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package com.sun.tools.jdi;
import com.sun.jdi.*;
import java.util.List;
import java.util.Map;
import java.util.Iterator;
import java.util.ListIterator;
import java.util.HashMap;
import java.util.ArrayList;
import java.util.Collections;
import java.lang.ref.SoftReference;
/**
* Represents methods with method bodies.
* That is, non-native non-abstract methods.
* Private to MethodImpl.
*/
public class ConcreteMethodImpl extends MethodImpl {
/*
* A subset of the line number info that is softly cached
*/
static private class SoftLocationXRefs {
final String stratumID; // The stratum of this information
final Map<Integer, List<Location>> lineMapper; // Maps line number to location(s)
final List<Location> lineLocations; // List of locations ordered by code index
/*
* Note: these do not necessarily correspond to
* the line numbers of the first and last elements
* in the lineLocations list. Use these only for bounds
* checking and with lineMapper.
*/
final int lowestLine;
final int highestLine;
SoftLocationXRefs(String stratumID, Map<Integer, List<Location>> lineMapper, List<Location> lineLocations,
int lowestLine, int highestLine) {
this.stratumID = stratumID;
this.lineMapper = Collections.unmodifiableMap(lineMapper);
this.lineLocations =
Collections.unmodifiableList(lineLocations);
this.lowestLine = lowestLine;
this.highestLine = highestLine;
}
}
private Location location = null;
private SoftReference<SoftLocationXRefs> softBaseLocationXRefsRef;
private SoftReference<SoftLocationXRefs> softOtherLocationXRefsRef;
private SoftReference<List<LocalVariable>> variablesRef = null;
private boolean absentVariableInformation = false;
private long firstIndex = -1;
private long lastIndex = -1;
private SoftReference<byte[]> bytecodesRef = null;
private int argSlotCount = -1;
ConcreteMethodImpl(VirtualMachine vm, ReferenceTypeImpl declaringType,
long ref,
String name, String signature,
String genericSignature, int modifiers) {
// The generic signature is set when this is created
super(vm, declaringType, ref, name, signature,
genericSignature, modifiers);
}
public Location location() {
if (location == null) {
getBaseLocations();
}
return location;
}
List<Location> sourceNameFilter(List<Location> list,
SDE.Stratum stratum,
String sourceName)
throws AbsentInformationException {
if (sourceName == null) {
return list;
} else {
/* needs sourceName filteration */
List<Location> locs = new ArrayList<Location>();
for (Location loc : list) {
if (((LocationImpl)loc).sourceName(stratum).equals(sourceName)) {
locs.add(loc);
}
}
return locs;
}
}
List<Location> allLineLocations(SDE.Stratum stratum,
String sourceName)
throws AbsentInformationException {
List<Location> lineLocations = getLocations(stratum).lineLocations;
if (lineLocations.size() == 0) {
throw new AbsentInformationException();
}
return Collections.unmodifiableList(
sourceNameFilter(lineLocations, stratum, sourceName));
}
List<Location> locationsOfLine(SDE.Stratum stratum,
String sourceName,
int lineNumber)
throws AbsentInformationException {
SoftLocationXRefs info = getLocations(stratum);
if (info.lineLocations.size() == 0) {
throw new AbsentInformationException();
}
/*
* Find the locations which match the line number
* passed in.
*/
List<Location> list = info.lineMapper.get(new Integer(lineNumber));
if (list == null) {
list = new ArrayList<Location>(0);
}
return Collections.unmodifiableList(
sourceNameFilter(list, stratum, sourceName));
}
public Location locationOfCodeIndex(long codeIndex) {
if (firstIndex == -1) {
getBaseLocations();
}
/*
* Check for invalid code index.
*/
if (codeIndex < firstIndex || codeIndex > lastIndex) {
return null;
}
return new LocationImpl(virtualMachine(), this, codeIndex);
}
LineInfo codeIndexToLineInfo(SDE.Stratum stratum,
long codeIndex) {
if (firstIndex == -1) {
getBaseLocations();
}
/*
* Check for invalid code index.
*/
if (codeIndex < firstIndex || codeIndex > lastIndex) {
throw new InternalError(
"Location with invalid code index");
}
List<Location> lineLocations = getLocations(stratum).lineLocations;
/*
* Check for absent line numbers.
*/
if (lineLocations.size() == 0) {
return super.codeIndexToLineInfo(stratum, codeIndex);
}
Iterator<Location> iter = lineLocations.iterator();
/*
* Treat code before the beginning of the first line table
* entry as part of the first line. javac will generate
* code like this for some local classes. This "prolog"
* code contains assignments from locals in the enclosing
* scope to synthetic fields in the local class. Same for
* other language prolog code.
*/
LocationImpl bestMatch = (LocationImpl)iter.next();
while (iter.hasNext()) {
LocationImpl current = (LocationImpl)iter.next();
if (current.codeIndex() > codeIndex) {
break;
}
bestMatch = current;
}
return bestMatch.getLineInfo(stratum);
}
public List<LocalVariable> variables() throws AbsentInformationException {
return getVariables();
}
public List<LocalVariable> variablesByName(String name) throws AbsentInformationException {
List<LocalVariable> variables = getVariables();
List<LocalVariable> retList = new ArrayList<LocalVariable>(2);
Iterator<LocalVariable> iter = variables.iterator();
while(iter.hasNext()) {
LocalVariable variable = iter.next();
if (variable.name().equals(name)) {
retList.add(variable);
}
}
return retList;
}
public List<LocalVariable> arguments() throws AbsentInformationException {
List<LocalVariable> variables = getVariables();
List<LocalVariable> retList = new ArrayList<LocalVariable>(variables.size());
Iterator<LocalVariable> iter = variables.iterator();
while(iter.hasNext()) {
LocalVariable variable = iter.next();
if (variable.isArgument()) {
retList.add(variable);
}
}
return retList;
}
public byte[] bytecodes() {
byte[] bytecodes = (bytecodesRef == null) ? null :
bytecodesRef.get();
if (bytecodes == null) {
try {
bytecodes = JDWP.Method.Bytecodes.
process(vm, declaringType, ref).bytes;
} catch (JDWPException exc) {
throw exc.toJDIException();
}
bytecodesRef = new SoftReference<byte[]>(bytecodes);
}
/*
* Arrays are always modifiable, so it is a little unsafe
* to return the cached bytecodes directly; instead, we
* make a clone at the cost of using more memory.
*/
return bytecodes.clone();
}
int argSlotCount() throws AbsentInformationException {
if (argSlotCount == -1) {
getVariables();
}
return argSlotCount;
}
private SoftLocationXRefs getLocations(SDE.Stratum stratum) {
if (stratum.isJava()) {
return getBaseLocations();
}
String stratumID = stratum.id();
SoftLocationXRefs info =
(softOtherLocationXRefsRef == null) ? null :
softOtherLocationXRefsRef.get();
if (info != null && info.stratumID.equals(stratumID)) {
return info;
}
List<Location> lineLocations = new ArrayList<Location>();
Map<Integer, List<Location>> lineMapper = new HashMap<Integer, List<Location>>();
int lowestLine = -1;
int highestLine = -1;
SDE.LineStratum lastLineStratum = null;
SDE.Stratum baseStratum =
declaringType.stratum(SDE.BASE_STRATUM_NAME);
Iterator<Location> it = getBaseLocations().lineLocations.iterator();
while(it.hasNext()) {
LocationImpl loc = (LocationImpl)it.next();
int baseLineNumber = loc.lineNumber(baseStratum);
SDE.LineStratum lineStratum =
stratum.lineStratum(declaringType,
baseLineNumber);
if (lineStratum == null) {
// location not mapped in this stratum
continue;
}
int lineNumber = lineStratum.lineNumber();
// remove unmapped and dup lines
if ((lineNumber != -1) &&
(!lineStratum.equals(lastLineStratum))) {
lastLineStratum = lineStratum;
// Remember the largest/smallest line number
if (lineNumber > highestLine) {
highestLine = lineNumber;
}
if ((lineNumber < lowestLine) || (lowestLine == -1)) {
lowestLine = lineNumber;
}
loc.addStratumLineInfo(
new StratumLineInfo(stratumID,
lineNumber,
lineStratum.sourceName(),
lineStratum.sourcePath()));
// Add to the location list
lineLocations.add(loc);
// Add to the line -> locations map
Integer key = new Integer(lineNumber);
List<Location> mappedLocs = lineMapper.get(key);
if (mappedLocs == null) {
mappedLocs = new ArrayList<Location>(1);
lineMapper.put(key, mappedLocs);
}
mappedLocs.add(loc);
}
}
info = new SoftLocationXRefs(stratumID,
lineMapper, lineLocations,
lowestLine, highestLine);
softOtherLocationXRefsRef = new SoftReference<SoftLocationXRefs>(info);
return info;
}
private SoftLocationXRefs getBaseLocations() {
SoftLocationXRefs info = (softBaseLocationXRefsRef == null) ? null :
softBaseLocationXRefsRef.get();
if (info != null) {
return info;
}
JDWP.Method.LineTable lntab = null;
try {
lntab = JDWP.Method.LineTable.process(vm, declaringType, ref);
} catch (JDWPException exc) {
/*
* Note: the absent info error shouldn't happen here
* because the first and last index are always available.
*/
throw exc.toJDIException();
}
int count = lntab.lines.length;
List<Location> lineLocations = new ArrayList<Location>(count);
Map<Integer, List<Location>>lineMapper = new HashMap<Integer, List<Location>>();
int lowestLine = -1;
int highestLine = -1;
for (int i = 0; i < count; i++) {
long bci = lntab.lines[i].lineCodeIndex;
int lineNumber = lntab.lines[i].lineNumber;
/*
* Some compilers will point multiple consecutive
* lines at the same location. We need to choose
* one of them so that we can consistently map back
* and forth between line and location. So we choose
* to record only the last line entry at a particular
* location.
*/
if ((i + 1 == count) || (bci != lntab.lines[i+1].lineCodeIndex)) {
// Remember the largest/smallest line number
if (lineNumber > highestLine) {
highestLine = lineNumber;
}
if ((lineNumber < lowestLine) || (lowestLine == -1)) {
lowestLine = lineNumber;
}
LocationImpl loc =
new LocationImpl(virtualMachine(), this, bci);
loc.addBaseLineInfo(
new BaseLineInfo(lineNumber, declaringType));
// Add to the location list
lineLocations.add(loc);
// Add to the line -> locations map
Integer key = new Integer(lineNumber);
List<Location> mappedLocs = lineMapper.get(key);
if (mappedLocs == null) {
mappedLocs = new ArrayList<Location>(1);
lineMapper.put(key, mappedLocs);
}
mappedLocs.add(loc);
}
}
/*
* firstIndex, lastIndex, and startLocation need to be
* retrieved only once since they are strongly referenced.
*/
if (location == null) {
firstIndex = lntab.start;
lastIndex = lntab.end;
/*
* The startLocation is the first one in the
* location list if we have one;
* otherwise, we construct a location for a
* method start with no line info
*/
if (count > 0) {
location = lineLocations.get(0);
} else {
location = new LocationImpl(virtualMachine(), this,
firstIndex);
}
}
info = new SoftLocationXRefs(SDE.BASE_STRATUM_NAME,
lineMapper, lineLocations,
lowestLine, highestLine);
softBaseLocationXRefsRef = new SoftReference<SoftLocationXRefs>(info);
return info;
}
private List<LocalVariable> getVariables1_4() throws AbsentInformationException {
JDWP.Method.VariableTable vartab = null;
try {
vartab = JDWP.Method.VariableTable.
process(vm, declaringType, ref);
} catch (JDWPException exc) {
if (exc.errorCode() == JDWP.Error.ABSENT_INFORMATION) {
absentVariableInformation = true;
throw new AbsentInformationException();
} else {
throw exc.toJDIException();
}
}
// Get the number of slots used by argument variables
argSlotCount = vartab.argCnt;
int count = vartab.slots.length;
List<LocalVariable> variables = new ArrayList<LocalVariable>(count);
for (int i=0; i<count; i++) {
JDWP.Method.VariableTable.SlotInfo si = vartab.slots[i];
/*
* Skip "this*" entries because they are never real
* variables from the JLS perspective.
*/
if (!si.name.startsWith("this$") && !si.name.equals("this")) {
Location scopeStart = new LocationImpl(virtualMachine(),
this, si.codeIndex);
Location scopeEnd =
new LocationImpl(virtualMachine(), this,
si.codeIndex + si.length - 1);
LocalVariable variable =
new LocalVariableImpl(virtualMachine(), this,
si.slot, scopeStart, scopeEnd,
si.name, si.signature, null);
// Add to the variable list
variables.add(variable);
}
}
return variables;
}
private List<LocalVariable> getVariables1() throws AbsentInformationException {
if (!vm.canGet1_5LanguageFeatures()) {
return getVariables1_4();
}
JDWP.Method.VariableTableWithGeneric vartab = null;
try {
vartab = JDWP.Method.VariableTableWithGeneric.
process(vm, declaringType, ref);
} catch (JDWPException exc) {
if (exc.errorCode() == JDWP.Error.ABSENT_INFORMATION) {
absentVariableInformation = true;
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