package org.springframework.orm.jpa.persistenceunit;
import java.lang.instrument.ClassFileTransformer;
import java.security.ProtectionDomain;
import javax.persistence.spi.ClassTransformer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
class ClassFileTransformerAdapter implements ClassFileTransformer {
private static final Log logger = LogFactory.getLog(ClassFileTransformerAdapter.class);
private final ClassTransformer classTransformer;
private boolean currentlyTransforming = false;
public ClassFileTransformerAdapter(ClassTransformer classTransformer) {
Assert.notNull(classTransformer, "ClassTransformer must not be null");
this.classTransformer = classTransformer;
}
@Override
@Nullable
public byte[] transform(
ClassLoader loader, String className, Class<?> classBeingRedefined,
ProtectionDomain protectionDomain, byte[] classfileBuffer) {
synchronized (this) {
if (this.currentlyTransforming) {
return null;
}
this.currentlyTransforming = true;
try {
byte[] transformed = this.classTransformer.transform(
loader, className, classBeingRedefined, protectionDomain, classfileBuffer);
if (transformed != null && logger.isDebugEnabled()) {
logger.debug("Transformer of class [" + this.classTransformer.getClass().getName() +
"] transformed class [" + className + "]; bytes in=" +
classfileBuffer.length + "; bytes out=" + transformed.length);
}
return transformed;
}
catch (ClassCircularityError ex) {
if (logger.isErrorEnabled()) {
logger.error("Circularity error while weaving class [" + className + "] with " +
"transformer of class [" + this.classTransformer.getClass().getName() + "]", ex);
}
throw new IllegalStateException("Failed to weave class [" + className + "]", ex);
}
catch (Throwable ex) {
if (logger.isWarnEnabled()) {
logger.warn("Error weaving class [" + className + "] with transformer of class [" +
this.classTransformer.getClass().getName() + "]", ex);
}
throw new IllegalStateException("Could not weave class [" + className + "]", ex);
}
finally {
this.currentlyTransforming = false;
}
}
}
@Override
public String toString() {
return "Standard ClassFileTransformer wrapping JPA transformer: " + this.classTransformer;
}
}