/**
* Copyright (c) 2014 Eclectic Logic LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package com.eclecticlogic.pedal.dialect.postgresql;
import java.io.Serializable;
import java.io.StringReader;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import javassist.CannotCompileException;
import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtNewMethod;
import javassist.NotFoundException;
import javax.persistence.Column;
import javax.persistence.Convert;
import javax.persistence.EntityManager;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import org.postgresql.copy.CopyManager;
import org.postgresql.core.BaseConnection;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.eclecticlogic.pedal.provider.ConnectionAccessor;
import com.eclecticlogic.pedal.spi.ProviderAccessSpi;
import com.google.common.base.Strings;
import com.google.common.base.Throwables;
/**
* Limitation in current implementation:
* 1. @Column annotation must be present on getters
* 2. @Column annotation should have column name in it.
* 3. @Convert annotation should be on getter
* 4. Array types can only be arrays of primitives. Bit arrays are supported. Annotate with @BitString
* 5. No embedded id support in entity or fk in entity.
* 6. No support for custom types.
* 7. No specific distinction between Temporal TIMESTAMP and DATE.
* @author kabram.
*
*/
public class CopyCommand {
private ConnectionAccessor connectionAccessor;
private ProviderAccessSpi providerAccessSpi;
private ConcurrentHashMap<Class<? extends Serializable>, String> fieldNamesByClass = new ConcurrentHashMap<>();
private ConcurrentHashMap<Class<? extends Serializable>, CopyExtractor<? extends Serializable>> extractorsByClass = new ConcurrentHashMap<>();
private static Logger logger = LoggerFactory.getLogger(CopyCommand.class);
public void setConnectionAccessor(ConnectionAccessor connectionAccessor) {
this.connectionAccessor = connectionAccessor;
}
public void setProviderAccessSpi(ProviderAccessSpi providerAccessSpi) {
this.providerAccessSpi = providerAccessSpi;
}
/**
* @param lists Entities to be inserted using the Postgres COPY command.
*/
public <E extends Serializable> void insert(EntityManager entityManager, CopyList<E> entityList) {
if (entityList.size() > 0) {
_insert(entityManager, entityList);
}
}
@SuppressWarnings("unchecked")
private <E extends Serializable> void _insert(EntityManager entityManager, CopyList<E> entityList) {
Class<? extends Serializable> clz = entityList.get(0).getClass();
setupFor(clz);
String fieldNames = fieldNamesByClass.get(clz);
CopyExtractor<E> extractor = (CopyExtractor<E>) extractorsByClass.get(clz);
StringBuilder builder = new StringBuilder(1024 * entityList.size());
for (E entity : entityList) {
builder.append(extractor.getValueList(entity));
builder.append("\n");
}
StringReader reader = new StringReader(builder.toString());
providerAccessSpi.run(
entityManager,
connection -> {
try {
CopyManager copyManager = new CopyManager((BaseConnection) connectionAccessor
.getRawConnection(connection));
long t1 = System.currentTimeMillis();
copyManager.copyIn("copy " + getEntityName(entityList) + "(" + fieldNames + ") from stdin",
reader);
long elapsedTime = System.currentTimeMillis() - t1;
logger.debug("Wrote {} inserts in {} seconds", entityList.size(),
Math.round(elapsedTime / 10.0) / 100.0);
} catch (Exception e) {
logger.trace("Command passed: copy {} ( {} ) from stdin {}", getEntityName(entityList),
fieldNames, builder);
throw Throwables.propagate(e);
}
});
}
private void setupFor(Class<? extends Serializable> clz) {
if (fieldNamesByClass.get(clz) == null) {
List<String> fields = new ArrayList<>();
List<Method> methods = new ArrayList<>();
for (Method method : clz.getMethods()) {
String columnName = null;
if (method.isAnnotationPresent(Id.class) && method.isAnnotationPresent(GeneratedValue.class)
&& method.getAnnotation(GeneratedValue.class).strategy() == GenerationType.IDENTITY) {
// Ignore pk with identity strategy.
} else if (method.isAnnotationPresent(Column.class)) {
columnName = method.getAnnotation(Column.class).name();
} else if (method.isAnnotationPresent(JoinColumn.class)
&& method.getAnnotation(JoinColumn.class).insertable()) {
columnName = method.getAnnotation(JoinColumn.class).name();
}
if (columnName != null) {
// Certain one-to-on join situations can lead to multiple columns with the same column-name.
if (!fields.contains(columnName)) {
fields.add(columnName);
methods.add(method);
}
} // end if annotation present
}
extractorsByClass.put(clz, getExtractor(clz, methods));
fieldNamesByClass.put(clz, String.join(",", fields));
}
}
/**
* Revisit this after javassist support java 8
*/
@SuppressWarnings({ "unchecked" })
private <E extends Serializable> CopyExtractor<E> getExtractor(Class<E> clz, List<Method> fieldMethods) {
ClassPool pool = ClassPool.getDefault();
CtClass cc = pool.makeClass("com.eclecticlogic.pedal.dialect.postgresql." + clz.getSimpleName()
+ "$CopyExtractor");
StringBuilder methodBody = new StringBuilder();
try {
cc.addInterface(pool.getCtClass(CopyExtractor.class.getName()));
methodBody.append("public String getValueList(Object entity) {\n");
methodBody.append("try {\n");
methodBody.append("StringBuilder builder = new StringBuilder();\n");
methodBody.append(clz.getName() + " typed = (" + clz.getName() + ")entity;\n");
for (int i = 0; i < fieldMethods.size(); i++) {
Method method = fieldMethods.get(i);
if (method.getReturnType().isPrimitive()) {
methodBody.append("builder.append(typed." + method.getName() + "());\n");
} else {
methodBody.append(method.getReturnType().getName() + " v" + i + " = typed." + method.getName()
+ "();\n");
methodBody.append("if (v" + i + " == null) {builder.append(\"\\\\N\");}\n");
methodBody.append("else {\n");
if (method.isAnnotationPresent(CopyAsBitString.class)) {
methodBody.append("java.util.Iterator it" + i + " = typed." + method.getName()
+ "().iterator();\n");
methodBody.append("while (it" + i + ".hasNext()) {\n");
methodBody.append("Boolean b = (Boolean)it" + i + ".next();\n");
methodBody.append("builder.append(b.booleanValue() ? \"0\" : \"1\");\n");
methodBody.append("}\n");
} else if (Collection.class.isAssignableFrom(method.getReturnType())
&& method.isAnnotationPresent(Convert.class) == false) {
// Postgreql array type.
if (method.isAnnotationPresent(CopyEmptyAsNull.class)) {
methodBody.append("if (typed." + method.getName() + "().isEmpty()) {\n");
methodBody.append("builder.append(\"\\\\N\");\n");
methodBody.append("} else {\n");
collectionExtractor(methodBody, i, method);
methodBody.append("}\n");
} else {
collectionExtractor(methodBody, i, method);
}
} else if (method.isAnnotationPresent(Convert.class)) {
Class<?> converterClass = method.getAnnotation(Convert.class).converter();
methodBody.append(converterClass.getName() + " c" + i + " = (" + converterClass.getName() + ")"
+ converterClass.getName() + ".class.newInstance();\n");
methodBody.append("builder.append(c" + i + ".convertToDatabaseColumn(v" + i + "));\n");
} else if (method.isAnnotationPresent(JoinColumn.class)) {
// We need to get the id of the joined object.
for (Method method2 : method.getReturnType().getMethods()) {
if (method2.isAnnotationPresent(Id.class)) {
methodBody.append("builder.append(v" + i + "." + method2.getName() + "());\n");
}
}
} else {
methodBody.append("builder.append(v" + i + ");\n");
}
methodBody.append("}\n");
}
if (i != fieldMethods.size() - 1) {
methodBody.append("builder.append(\"\\t\");\n");
}
}
methodBody.append("return builder.toString();\n");
methodBody.append("} catch (Exception e) { throw new RuntimeException(e); } \n");
methodBody.append("}\n");
logger.trace(methodBody.toString());
cc.addMethod(CtNewMethod.make(methodBody.toString(), cc));
} catch (NotFoundException | CannotCompileException e) {
logger.error(e.getMessage(), "Compiled body is:\n" + methodBody.toString());
throw Throwables.propagate(e);
}
try {
return (CopyExtractor<E>) cc.toClass().newInstance();
} catch (InstantiationException | IllegalAccessException | CannotCompileException e) {
throw Throwables.propagate(e);
}
}
private void collectionExtractor(StringBuilder methodBody, int i, Method method) {
methodBody.append("java.util.Iterator it" + i + " = typed." + method.getName() + "().iterator();\n");
methodBody.append("StringBuilder array" + i + " = new StringBuilder();\n");
methodBody.append("while (it" + i + ".hasNext()) {\n");
methodBody.append("Object o = it" + i + ".next();\n");
methodBody.append("array" + i + ".append(\",\").append(o);\n");
methodBody.append("}\n");
methodBody.append("String arrayStr" + i + " = array" + i + ".length() == 0 ? \"\" : array" + i
+ ".substring(1);\n");
methodBody.append("builder.append(\"{\").append(arrayStr" + i + ").append(\"}\");\n");
}
private <E extends Serializable> String getEntityName(CopyList<E> copyList) {
if (Strings.isNullOrEmpty(copyList.getAlternateTableName())) {
return providerAccessSpi.getTableName(copyList.get(0).getClass());
} else {
String schemaName = providerAccessSpi.getSchemaName();
if (Strings.isNullOrEmpty(schemaName)) {
return copyList.getAlternateTableName();
} else {
return schemaName + "." + copyList.getAlternateTableName();
}
}
}
}