This example Java source code file (JavacState.java) is included in the alvinalexander.com
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* 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).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.tools.sjavac;
import java.io.*;
import java.util.Collections;
import java.util.Date;
import java.util.Set;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.HashMap;
import java.text.SimpleDateFormat;
import java.net.URI;
import java.util.*;
/**
* The javac state class maintains the previous (prev) and the current (now)
* build states and everything else that goes into the javac_state file.
*
* <p>This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own
* risk. This code and its internal interfaces are subject to change
* or deletion without notice.</b>
*/
public class JavacState
{
// The arguments to the compile. If not identical, then it cannot
// be an incremental build!
String theArgs;
// The number of cores limits how many threads are used for heavy concurrent work.
int numCores;
// The bin_dir/javac_state
private String javacStateFilename;
private File javacState;
// The previous build state is loaded from javac_state
private BuildState prev;
// The current build state is constructed during the build,
// then saved as the new javac_state.
private BuildState now;
// Something has changed in the javac_state. It needs to be saved!
private boolean needsSaving;
// If this is a new javac_state file, then do not print unnecessary messages.
private boolean newJavacState;
// These are packages where something has changed and the package
// needs to be recompiled. Actions that trigger recompilation:
// * source belonging to the package has changed
// * artifact belonging to the package is lost, or its timestamp has been changed.
// * an unknown artifact has appeared, we simply delete it, but we also trigger a recompilation.
// * a package that is tainted, taints all packages that depend on it.
private Set<String> taintedPackages;
// After a compile, the pubapis are compared with the pubapis stored in the javac state file.
// Any packages where the pubapi differ are added to this set.
// Later we use this set and the dependency information to taint dependent packages.
private Set<String> packagesWithChangedPublicApis;
// When a module-info.java file is changed, taint the module,
// then taint all modules that depend on that that module.
// A module dependency can occur directly through a require, or
// indirectly through a module that does a public export for the first tainted module.
// When all modules are tainted, then taint all packages belonging to these modules.
// Then rebuild. It is perhaps possible (and valuable?) to do a more finegrained examination of the
// change in module-info.java, but that will have to wait.
private Set<String> taintedModules;
// The set of all packages that has been recompiled.
// Copy over the javac_state for the packages that did not need recompilation,
// verbatim from the previous (prev) to the new (now) build state.
private Set<String> recompiledPackages;
// The output directories filled with tasty artifacts.
private File binDir, gensrcDir, headerDir;
// The current status of the file system.
private Set<File> binArtifacts;
private Set<File> gensrcArtifacts;
private Set<File> headerArtifacts;
// The status of the sources.
Set<Source> removedSources = null;
Set<Source> addedSources = null;
Set<Source> modifiedSources = null;
// Visible sources for linking. These are the only
// ones that -sourcepath is allowed to see.
Set<URI> visibleSrcs;
// Visible classes for linking. These are the only
// ones that -classpath is allowed to see.
// It maps from a classpath root to the set of visible classes for that root.
// If the set is empty, then all classes are visible for that root.
// It can also map from a jar file to the set of visible classes for that jar file.
Map<URI,Set visibleClasses;
// Setup two transforms that always exist.
private CopyFile copyFiles = new CopyFile();
private CompileJavaPackages compileJavaPackages = new CompileJavaPackages();
// Where to send stdout and stderr.
private PrintStream out, err;
JavacState(String[] args, File bd, File gd, File hd, boolean permitUnidentifiedArtifacts, boolean removeJavacState,
PrintStream o, PrintStream e) {
out = o;
err = e;
numCores = Main.findNumberOption(args, "-j");
theArgs = "";
for (String a : removeArgsNotAffectingState(args)) {
theArgs = theArgs+a+" ";
}
binDir = bd;
gensrcDir = gd;
headerDir = hd;
javacStateFilename = binDir.getPath()+File.separator+"javac_state";
javacState = new File(javacStateFilename);
if (removeJavacState && javacState.exists()) {
javacState.delete();
}
newJavacState = false;
if (!javacState.exists()) {
newJavacState = true;
// If there is no javac_state then delete the contents of all the artifact dirs!
// We do not want to risk building a broken incremental build.
// BUT since the makefiles still copy things straight into the bin_dir et al,
// we avoid deleting files here, if the option --permit-unidentified-classes was supplied.
if (!permitUnidentifiedArtifacts) {
deleteContents(binDir);
deleteContents(gensrcDir);
deleteContents(headerDir);
}
needsSaving = true;
}
prev = new BuildState();
now = new BuildState();
taintedPackages = new HashSet<String>();
recompiledPackages = new HashSet<String>();
packagesWithChangedPublicApis = new HashSet<String>();
}
public BuildState prev() { return prev; }
public BuildState now() { return now; }
/**
* Remove args not affecting the state.
*/
static String[] removeArgsNotAffectingState(String[] args) {
String[] out = new String[args.length];
int j = 0;
for (int i = 0; i<args.length; ++i) {
if (args[i].equals("-j")) {
// Just skip it and skip following value
i++;
} else if (args[i].startsWith("--server:")) {
// Just skip it.
} else if (args[i].startsWith("--log=")) {
// Just skip it.
} else if (args[i].equals("--compare-found-sources")) {
// Just skip it and skip verify file name
i++;
} else {
// Copy argument.
out[j] = args[i];
j++;
}
}
String[] ret = new String[j];
System.arraycopy(out, 0, ret, 0, j);
return ret;
}
/**
* Specify which sources are visible to the compiler through -sourcepath.
*/
public void setVisibleSources(Map<String,Source> vs) {
visibleSrcs = new HashSet<URI>();
for (String s : vs.keySet()) {
Source src = vs.get(s);
visibleSrcs.add(src.file().toURI());
}
}
/**
* Specify which classes are visible to the compiler through -classpath.
*/
public void setVisibleClasses(Map<String,Source> vs) {
visibleSrcs = new HashSet<URI>();
for (String s : vs.keySet()) {
Source src = vs.get(s);
visibleSrcs.add(src.file().toURI());
}
}
/**
* Returns true if this is an incremental build.
*/
public boolean isIncremental() {
return !prev.sources().isEmpty();
}
/**
* Find all artifacts that exists on disk.
*/
public void findAllArtifacts() {
binArtifacts = findAllFiles(binDir);
gensrcArtifacts = findAllFiles(gensrcDir);
headerArtifacts = findAllFiles(headerDir);
}
/**
* Lookup the artifacts generated for this package in the previous build.
*/
private Map<String,File> fetchPrevArtifacts(String pkg) {
Package p = prev.packages().get(pkg);
if (p != null) {
return p.artifacts();
}
return new HashMap<String,File>();
}
/**
* Delete all prev artifacts in the currently tainted packages.
*/
public void deleteClassArtifactsInTaintedPackages() {
for (String pkg : taintedPackages) {
Map<String,File> arts = fetchPrevArtifacts(pkg);
for (File f : arts.values()) {
if (f.exists() && f.getName().endsWith(".class")) {
f.delete();
}
}
}
}
/**
* Mark the javac_state file to be in need of saving and as a side effect,
* it gets a new timestamp.
*/
private void needsSaving() {
needsSaving = true;
}
/**
* Save the javac_state file.
*/
public void save() throws IOException {
if (!needsSaving) return;
try (FileWriter out = new FileWriter(javacStateFilename)) {
StringBuilder b = new StringBuilder();
long millisNow = System.currentTimeMillis();
Date d = new Date(millisNow);
SimpleDateFormat df =
new SimpleDateFormat("yyyy-MM-dd HH:mm:ss SSS");
b.append("# javac_state ver 0.3 generated "+millisNow+" "+df.format(d)+"\n");
b.append("# This format might change at any time. Please do not depend on it.\n");
b.append("# M module\n");
b.append("# P package\n");
b.append("# S C source_tobe_compiled timestamp\n");
b.append("# S L link_only_source timestamp\n");
b.append("# G C generated_source timestamp\n");
b.append("# A artifact timestamp\n");
b.append("# D dependency\n");
b.append("# I pubapi\n");
b.append("# R arguments\n");
b.append("R ").append(theArgs).append("\n");
// Copy over the javac_state for the packages that did not need recompilation.
now.copyPackagesExcept(prev, recompiledPackages, new HashSet<String>());
// Save the packages, ie package names, dependencies, pubapis and artifacts!
// I.e. the lot.
Module.saveModules(now.modules(), b);
String s = b.toString();
out.write(s, 0, s.length());
}
}
/**
* Load a javac_state file.
*/
public static JavacState load(String[] args, File binDir, File gensrcDir, File headerDir,
boolean permitUnidentifiedArtifacts, PrintStream out, PrintStream err) {
JavacState db = new JavacState(args, binDir, gensrcDir, headerDir, permitUnidentifiedArtifacts, false, out, err);
Module lastModule = null;
Package lastPackage = null;
Source lastSource = null;
boolean noFileFound = false;
boolean foundCorrectVerNr = false;
boolean newCommandLine = false;
boolean syntaxError = false;
try (BufferedReader in = new BufferedReader(new FileReader(db.javacStateFilename))) {
for (;;) {
String l = in.readLine();
if (l==null) break;
if (l.length()>=3 && l.charAt(1) == ' ') {
char c = l.charAt(0);
if (c == 'M') {
lastModule = db.prev.loadModule(l);
} else
if (c == 'P') {
if (lastModule == null) { syntaxError = true; break; }
lastPackage = db.prev.loadPackage(lastModule, l);
} else
if (c == 'D') {
if (lastModule == null || lastPackage == null) { syntaxError = true; break; }
lastPackage.loadDependency(l);
} else
if (c == 'I') {
if (lastModule == null || lastPackage == null) { syntaxError = true; break; }
lastPackage.loadPubapi(l);
} else
if (c == 'A') {
if (lastModule == null || lastPackage == null) { syntaxError = true; break; }
lastPackage.loadArtifact(l);
} else
if (c == 'S') {
if (lastModule == null || lastPackage == null) { syntaxError = true; break; }
lastSource = db.prev.loadSource(lastPackage, l, false);
} else
if (c == 'G') {
if (lastModule == null || lastPackage == null) { syntaxError = true; break; }
lastSource = db.prev.loadSource(lastPackage, l, true);
} else
if (c == 'R') {
String ncmdl = "R "+db.theArgs;
if (!l.equals(ncmdl)) {
newCommandLine = true;
}
} else
if (c == '#') {
if (l.startsWith("# javac_state ver ")) {
int sp = l.indexOf(" ", 18);
if (sp != -1) {
String ver = l.substring(18,sp);
if (!ver.equals("0.3")) {
break;
}
foundCorrectVerNr = true;
}
}
}
}
}
} catch (FileNotFoundException e) {
// Silently create a new javac_state file.
noFileFound = true;
} catch (IOException e) {
Log.info("Dropping old javac_state because of errors when reading it.");
db = new JavacState(args, binDir, gensrcDir, headerDir, permitUnidentifiedArtifacts, true, out, err);
foundCorrectVerNr = true;
newCommandLine = false;
syntaxError = false;
}
if (foundCorrectVerNr == false && !noFileFound) {
Log.info("Dropping old javac_state since it is of an old version.");
db = new JavacState(args, binDir, gensrcDir, headerDir, permitUnidentifiedArtifacts, true, out, err);
} else
if (newCommandLine == true && !noFileFound) {
Log.info("Dropping old javac_state since a new command line is used!");
db = new JavacState(args, binDir, gensrcDir, headerDir, permitUnidentifiedArtifacts, true, out, err);
} else
if (syntaxError == true) {
Log.info("Dropping old javac_state since it contains syntax errors.");
db = new JavacState(args, binDir, gensrcDir, headerDir, permitUnidentifiedArtifacts, true, out, err);
}
db.prev.calculateDependents();
return db;
}
/**
* Mark a java package as tainted, ie it needs recompilation.
*/
public void taintPackage(String name, String because) {
if (!taintedPackages.contains(name)) {
if (because != null) Log.debug("Tainting "+Util.justPackageName(name)+" because "+because);
// It has not been tainted before.
taintedPackages.add(name);
needsSaving();
Package nowp = now.packages().get(name);
if (nowp != null) {
for (String d : nowp.dependents()) {
taintPackage(d, because);
}
}
}
}
/**
* This packages need recompilation.
*/
public Set<String> taintedPackages() {
return taintedPackages;
}
/**
* Clean out the tainted package set, used after the first round of compiles,
* prior to propagating dependencies.
*/
public void clearTaintedPackages() {
taintedPackages = new HashSet<String>();
}
/**
* Go through all sources and check which have been removed, added or modified
* and taint the corresponding packages.
*/
public void checkSourceStatus(boolean check_gensrc) {
removedSources = calculateRemovedSources();
for (Source s : removedSources) {
if (!s.isGenerated() || check_gensrc) {
taintPackage(s.pkg().name(), "source "+s.name()+" was removed");
}
}
addedSources = calculateAddedSources();
for (Source s : addedSources) {
String msg = null;
if (isIncremental()) {
// When building from scratch, there is no point
// printing "was added" for every file since all files are added.
// However for an incremental build it makes sense.
msg = "source "+s.name()+" was added";
}
if (!s.isGenerated() || check_gensrc) {
taintPackage(s.pkg().name(), msg);
}
}
modifiedSources = calculateModifiedSources();
for (Source s : modifiedSources) {
if (!s.isGenerated() || check_gensrc) {
taintPackage(s.pkg().name(), "source "+s.name()+" was modified");
}
}
}
/**
* Acquire the compile_java_packages suffix rule for .java files.
*/
public Map<String,Transformer> getJavaSuffixRule() {
Map<String,Transformer> sr = new HashMap();
sr.put(".java", compileJavaPackages);
return sr;
}
/**
* Acquire the copying transform.
*/
public Transformer getCopier() {
return copyFiles;
}
/**
* If artifacts have gone missing, force a recompile of the packages
* they belong to.
*/
public void taintPackagesThatMissArtifacts() {
for (Package pkg : prev.packages().values()) {
for (File f : pkg.artifacts().values()) {
if (!f.exists()) {
// Hmm, the artifact on disk does not exist! Someone has removed it....
// Lets rebuild the package.
taintPackage(pkg.name(), ""+f+" is missing.");
}
}
}
}
/**
* Propagate recompilation through the dependency chains.
* Avoid re-tainting packages that have already been compiled.
*/
public void taintPackagesDependingOnChangedPackages(Set<String> pkgs, Set recentlyCompiled) {
for (Package pkg : prev.packages().values()) {
for (String dep : pkg.dependencies()) {
if (pkgs.contains(dep) && !recentlyCompiled.contains(pkg.name())) {
taintPackage(pkg.name(), " its depending on "+dep);
}
}
}
}
/**
* Scan all output dirs for artifacts and remove those files (artifacts?)
* that are not recognized as such, in the javac_state file.
*/
public void removeUnidentifiedArtifacts() {
Set<File> allKnownArtifacts = new HashSet();
for (Package pkg : prev.packages().values()) {
for (File f : pkg.artifacts().values()) {
allKnownArtifacts.add(f);
}
}
// Do not forget about javac_state....
allKnownArtifacts.add(javacState);
for (File f : binArtifacts) {
if (!allKnownArtifacts.contains(f)) {
Log.debug("Removing "+f.getPath()+" since it is unknown to the javac_state.");
f.delete();
}
}
for (File f : headerArtifacts) {
if (!allKnownArtifacts.contains(f)) {
Log.debug("Removing "+f.getPath()+" since it is unknown to the javac_state.");
f.delete();
}
}
for (File f : gensrcArtifacts) {
if (!allKnownArtifacts.contains(f)) {
Log.debug("Removing "+f.getPath()+" since it is unknown to the javac_state.");
f.delete();
}
}
}
/**
* Remove artifacts that are no longer produced when compiling!
*/
public void removeSuperfluousArtifacts(Set<String> recentlyCompiled) {
// Nothing to do, if nothing was recompiled.
if (recentlyCompiled.size() == 0) return;
for (String pkg : now.packages().keySet()) {
// If this package has not been recompiled, skip the check.
if (!recentlyCompiled.contains(pkg)) continue;
Collection<File> arts = now.artifacts().values();
for (File f : fetchPrevArtifacts(pkg).values()) {
if (!arts.contains(f)) {
Log.debug("Removing "+f.getPath()+" since it is now superfluous!");
if (f.exists()) f.delete();
}
}
}
}
/**
* Return those files belonging to prev, but not now.
*/
private Set<Source> calculateRemovedSources() {
Set<Source> removed = new HashSet
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