/*
* Copyright © 2012-2013 mumu@yfyang. All Rights Reserved.
*/
package org.mybatis.pagination;
import com.google.common.base.Joiner;
import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
import io.github.sparta.helpers.reflex.Reflections;
import io.github.sparta.helpers.sql.SqlRemoveHelper;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.logging.Log;
import org.apache.ibatis.logging.LogFactory;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.plugin.*;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
import org.mybatis.pagination.dialect.DBMS;
import org.mybatis.pagination.dialect.Dialect;
import org.mybatis.pagination.dialect.DialectClient;
import org.mybatis.pagination.dto.datatables.PagingCriteria;
import org.mybatis.pagination.dto.datatables.SearchField;
import org.mybatis.pagination.dto.datatables.SortField;
import org.mybatis.pagination.helpers.CountHelper;
import org.mybatis.pagination.helpers.StringHelper;
import java.io.Serializable;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;
import java.util.Properties;
/**
* <p>
* Mybatis数据库分页插件.
* 拦截StatementHandler的prepare方法
* </p>
*
* @author poplar.yfyang
* @version 1.0 2011-11-18 下午12:31
* @since JDK 1.5
*/
@Intercepts({@Signature(
type = Executor.class,
method = "query",
args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class})})
public class PaginationInterceptor implements Interceptor, Serializable {
/** serial Version */
private static final long serialVersionUID = -6075937069117597841L;
private static final ThreadLocal<Integer> PAGINATION_TOTAL = new ThreadLocal<Integer>();
private static final ThreadLocal<PagingCriteria> PAGE_REQUEST = new ThreadLocal<PagingCriteria>();
/** logging */
private static final Log log = LogFactory.getLog(PaginationInterceptor.class);
/** mapped statement parameter index. */
private static final int MAPPED_STATEMENT_INDEX = 0;
/** sql id , in the mapper xml file. */
private static String _sql_regex = "[*]";
/** DataBase dialect. */
protected Dialect _dialect;
/**
* Gets pagination total.
*
* @return the pagination total
*/
public static int getPaginationTotal() {
if (PAGINATION_TOTAL.get() == null) {
return 0;
}
return PAGINATION_TOTAL.get();
}
/**
* Gets page request.
*
* @return the page request
*/
public static PagingCriteria getPageRequest() {
return PAGE_REQUEST.get();
}
/** clear total context. */
public static void clean() {
PAGE_REQUEST.remove();
PAGINATION_TOTAL.remove();
}
/**
* Set the paging information,to RowBuounds.
*
* @param rowBounds rowBounds.
* @return rowBounds.
*/
private static RowBounds offset_paging(RowBounds rowBounds, PagingCriteria pageRequest) {
// rowBuounds has offset.
if (rowBounds.getOffset() == RowBounds.NO_ROW_OFFSET) {
if (pageRequest != null) {
return new RowBounds(pageRequest.getDisplayStart(), pageRequest.getDisplaySize());
}
}
return rowBounds;
}
/**
* Sort and filter sql.
*
*
* @param sql the sql
* @param pagingCriteria the paging criteria
* @return the string
*/
private static String sortAndFilterSql(String sql, PagingCriteria pagingCriteria) {
boolean order = SqlRemoveHelper.containOrder(sql);
final List<SearchField> searchFields = pagingCriteria.getSearchFields();
if (searchFields != null && !searchFields.isEmpty()) {
List<String> where_field = Lists.newArrayList();
for (SearchField searchField : searchFields) {
// fix inject sql
where_field.add(searchField.getField() + StringHelper.LIKE_CHAR + StringHelper.likeValue(searchField.getValue()));
}
boolean where = SqlRemoveHelper.containWhere(sql);
String orderBy = StringHelper.EMPTY;
if (order) {
String[] sqls = sql.split(SqlRemoveHelper.ORDER_REGEX);
sql = sqls[0];
orderBy = CountHelper.SQL_ORDER + sqls[1];
}
sql = String.format((where ? CountHelper.OR_SQL_FORMAT : CountHelper.WHERE_SQL_FORMAT), sql
, Joiner.on(CountHelper.OR_JOINER).skipNulls().join(where_field), orderBy);
}
final List<SortField> sortFields = pagingCriteria.getSortFields();
if (sortFields != null && !sortFields.isEmpty()) {
List<String> field_order = Lists.newArrayList();
for (SortField sortField : sortFields) {
field_order.add(sortField.getField() + StringHelper.BLANK_CHAR + sortField.getDirection().getDirection());
}
return String.format(order ? CountHelper.SQL_FORMAT : CountHelper.ORDER_SQL_FORMAT, sql
, Joiner.on(StringHelper.DOT_CHAR).skipNulls().join(field_order));
}
return sql;
}
/**
* Copy from bound sql.
*
* @param ms the ms
* @param boundSql the bound sql
* @param sql the sql
* @return the bound sql
*/
public static BoundSql copyFromBoundSql(MappedStatement ms, BoundSql boundSql,
String sql) {
BoundSql newBoundSql = new BoundSql(ms.getConfiguration(), sql, boundSql.getParameterMappings(), boundSql.getParameterObject());
for (ParameterMapping mapping : boundSql.getParameterMappings()) {
String prop = mapping.getProperty();
if (boundSql.hasAdditionalParameter(prop)) {
newBoundSql.setAdditionalParameter(prop, boundSql.getAdditionalParameter(prop));
}
}
return newBoundSql;
}
//see: MapperBuilderAssistant
private static MappedStatement copyFromMappedStatement(MappedStatement ms, SqlSource newSqlSource) {
MappedStatement.Builder builder = new MappedStatement.Builder(ms.getConfiguration(), ms.getId(), newSqlSource, ms.getSqlCommandType());
builder.resource(ms.getResource());
builder.fetchSize(ms.getFetchSize());
builder.statementType(ms.getStatementType());
builder.keyGenerator(ms.getKeyGenerator());
String[] keyProperties = ms.getKeyProperties();
builder.keyProperty(keyProperties == null ? null : keyProperties[0]);
//setStatementTimeout()
builder.timeout(ms.getTimeout());
//setStatementResultMap()
builder.parameterMap(ms.getParameterMap());
//setStatementResultMap()
builder.resultMaps(ms.getResultMaps());
builder.resultSetType(ms.getResultSetType());
//setStatementCache()
builder.cache(ms.getCache());
builder.flushCacheRequired(ms.isFlushCacheRequired());
builder.useCache(ms.isUseCache());
return builder.build();
}
/**
* perform paging intercetion.
*
* @param queryArgs Executor.query params.
*/
private void processIntercept(final Object[] queryArgs) {
final MappedStatement ms = (MappedStatement) queryArgs[MAPPED_STATEMENT_INDEX];
final Object parameter = queryArgs[1];
//the need for paging intercept.
boolean interceptor = ms.getId().matches(_sql_regex);
//obtain paging information.
final PagingCriteria pageRequest = interceptor
? PagingParametersFinder.instance.findCriteria(parameter)
: PagingCriteria.getDefaultCriteria();
PAGE_REQUEST.set(pageRequest);
final RowBounds oldRow = (RowBounds) queryArgs[2];
final RowBounds rowBounds = (interceptor) ? offset_paging(oldRow, pageRequest) : oldRow;
int offset = rowBounds.getOffset();
int limit = rowBounds.getLimit();
if (_dialect.supportsLimit() && (offset != RowBounds.NO_ROW_OFFSET || limit != RowBounds.NO_ROW_LIMIT)) {
final BoundSql boundSql = ms.getBoundSql(parameter);
String sql = boundSql.getSql().trim();
Connection connection = null;
try {
//get connection
connection = ms.getConfiguration().getEnvironment().getDataSource().getConnection();
int count = CountHelper.getCount(sql, connection, ms, parameter, boundSql, _dialect);
PAGINATION_TOTAL.set(count);
} catch (SQLException e) {
log.error("The total number of access to the database failure.", e);
} finally {
try {
if (connection != null && !connection.isClosed()) {
connection.close();
}
} catch (SQLException e) {
log.error("Close the database connection error.", e);
}
}
String new_sql = sortAndFilterSql(sql, pageRequest);
if (_dialect.supportsLimit()) {
new_sql = _dialect.getLimitString(new_sql, offset, limit);
offset = RowBounds.NO_ROW_OFFSET;
} else {
new_sql = _dialect.getLimitString(new_sql, 0, limit);
}
if (log.isDebugEnabled()) {
log.debug("pagination sql is :[" + new_sql + "]");
}
limit = RowBounds.NO_ROW_LIMIT;
queryArgs[2] = new RowBounds(offset, limit);
BoundSql newBoundSql = copyFromBoundSql(ms, boundSql, new_sql);
MappedStatement newMs = copyFromMappedStatement(ms, new BoundSqlSqlSource(newBoundSql));
queryArgs[MAPPED_STATEMENT_INDEX] = newMs;
}
}
@Override
public Object intercept(Invocation invocation) throws Throwable {
processIntercept(invocation.getArgs());
return invocation.proceed();
}
@Override
public Object plugin(Object o) {
if (Executor.class.isAssignableFrom(o.getClass())) {
return Plugin.wrap(new PaginationExecutor((Executor) o), this);
}
return Plugin.wrap(o, this);
}
/**
* 设置属性，支持自定义方言类和制定数据库的方式
* <p>
* <code>dialectClass</code>,自定义方言类。可以不配置这项
* <ode>dbms</ode> 数据库类型，插件支持的数据库
* <code>sqlRegex</code> 需要拦截的SQL ID
* </p>
* 如果同时配置了<code>dialectClass</code>和<code>dbms</code>,则以<code>dbms</code>为主
*
* @param p 属性
*/
@Override
public void setProperties(Properties p) {
String dialectClass = p.getProperty("dialectClass");
DBMS dbms;
if (StringHelper.isEmpty(dialectClass)) {
String dialect = p.getProperty("dbms");
Preconditions.checkArgument(!StringHelper.isEmpty(dialect), "dialect property is not found!");
dbms = DBMS.valueOf(dialect.toUpperCase());
Preconditions.checkNotNull(dbms, "plugin not super on this database.");
} else {
Dialect dialect1 = (Dialect) Reflections.instance(dialectClass);
Preconditions.checkNotNull(dialect1, "dialectClass is not found!");
DialectClient.putEx(dialect1);
dbms = DBMS.EX;
}
_dialect = DialectClient.getDbmsDialect(dbms);
String sql_regex = p.getProperty("sqlRegex");
if (!StringHelper.isEmpty(sql_regex)) {
_sql_regex = sql_regex;
}
clean();
}
public static class BoundSqlSqlSource implements SqlSource {
BoundSql boundSql;
public BoundSqlSqlSource(BoundSql boundSql) {
this.boundSql = boundSql;
}
public BoundSql getBoundSql(Object parameterObject) {
return boundSql;
}
}
}