package com.github.dynamicextensionsalfresco.osgi.spring;
import com.github.dynamicextensionsalfresco.osgi.Configuration;
import com.github.dynamicextensionsalfresco.osgi.JavaPackageScanner;
import com.github.dynamicextensionsalfresco.osgi.PackageCacheMode;
import com.github.dynamicextensionsalfresco.osgi.SystemPackage;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import java.io.*;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Set;
/**
* Provides {@link SystemPackage}s by scanning the web application for Java packages.
*
* @author Laurens Fridael
*
*/
public class WebApplicationSystemPackageFactoryBean implements FactoryBean<Set<SystemPackage>> {
private final Logger logger = LoggerFactory.getLogger(getClass());
/* Dependencies */
private ObjectFactory<JavaPackageScanner> javaPackageScanner;
private Configuration configuration;
/* Main operations */
@Override
public boolean isSingleton() {
return true;
}
@SuppressWarnings("unchecked")
@Override
public Class<? extends Set<SystemPackage>> getObjectType() {
return (Class<? extends Set<SystemPackage>>) (Class<?>) Set.class;
}
@Override
public Set<SystemPackage> getObject() throws Exception {
return createSystemPackages();
}
/* Utility operations */
protected Set<SystemPackage> createSystemPackages() {
final JavaPackageScanner packageScanner = javaPackageScanner.getObject();
final boolean validCache = packageScanner.isCacheValid(configuration.getSystemPackageCache());
Set<SystemPackage> packages;
if (validCache) {
packages = getCachedPackages();
} else {
packages = Collections.emptySet();
}
final boolean cacheDoesNotExist = CollectionUtils.isEmpty(packages);
final PackageCacheMode packageCacheMode = configuration.getSystemPackageCacheMode();
if (packageCacheMode.isReadFromCache() == false || cacheDoesNotExist || !validCache) {
packages = packageScanner.scanWebApplicationPackages();
}
if (packageCacheMode.isForceWriteToCache() || (cacheDoesNotExist && packageCacheMode.isWriteToCache())) {
writeCachedPackages(packages);
}
if (packageCacheMode.isWriteToCache() == false) {
final File cacheFile = configuration.getSystemPackageCache();
if (cacheFile.isFile()) {
cacheFile.delete();
}
}
return packages;
}
private Set<SystemPackage> getCachedPackages() {
File packageCache = configuration.getSystemPackageCache();
if (packageCache.isFile()) {
try {
final LineNumberReader in = new LineNumberReader(new InputStreamReader(new FileInputStream(packageCache)));
try {
final Set<SystemPackage> systemPackages = new LinkedHashSet<SystemPackage>(4500, 0.1f);
for (String line; (line = in.readLine()) != null;) {
line = line.trim();
if (line.isEmpty() == false) {
systemPackages.add(SystemPackage.fromString(line));
}
}
return systemPackages;
} catch (final IOException e) {
if (logger.isWarnEnabled()) {
logger.warn("Error reading cached system package configuration from repository: {}.",
e.getMessage());
}
} finally {
IOUtils.closeQuietly(in);
}
} catch (IOException e) {
logger.warn("Failed to open Java packages cache reader", e);
}
}
return null;
}
private void writeCachedPackages(final Set<SystemPackage> packages) {
final File packageCache = configuration.getSystemPackageCache();
PrintWriter writer = null;
try {
writer = new PrintWriter(new FileOutputStream(packageCache));
for (final SystemPackage systemPackage : packages) {
writer.println(systemPackage.toString());
}
logger.debug("Wrote system package list to {}.", packageCache.getAbsolutePath());
} catch (FileNotFoundException e) {
logger.warn("Failed t");
} finally {
IOUtils.closeQuietly(writer);
}
}
/* Dependencies */
public void setJavaPackageScanner(final ObjectFactory<JavaPackageScanner> javaPackageScanner) {
Assert.notNull(javaPackageScanner);
this.javaPackageScanner = javaPackageScanner;
}
/* Configuration */
public void setConfiguration(Configuration configuration) {
this.configuration = configuration;
}
}