com.eryansky.common.orm.mybatis.interceptor.PreparePaginationInterceptor.java Source code

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Here is the source code for com.eryansky.common.orm.mybatis.interceptor.PreparePaginationInterceptor.java

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/**
 *  Copyright (c) 2012-2014 http://www.eryansky.com
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 */
package com.eryansky.common.orm.mybatis.interceptor;

import com.eryansky.common.orm.Page;
import com.eryansky.common.utils.reflection.ReflectionUtils;
import org.apache.ibatis.executor.statement.BaseStatementHandler;
import org.apache.ibatis.executor.statement.RoutingStatementHandler;
import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;

import java.sql.Connection;
import java.util.Properties;

/**
 * Mybatis??StatementHandlerprepare
 * @author &Eryan eryanwcp@gmail.com
 * @version 2014-7-16
 */
@Intercepts({ @Signature(type = StatementHandler.class, method = "prepare", args = { Connection.class }) })
public class PreparePaginationInterceptor extends BaseInterceptor {

    private static final long serialVersionUID = 1L;

    public PreparePaginationInterceptor() {
        super();
    }

    @Override
    public Object intercept(Invocation ivk) throws Throwable {
        if (ivk.getTarget().getClass().isAssignableFrom(RoutingStatementHandler.class)) {
            final RoutingStatementHandler statementHandler = (RoutingStatementHandler) ivk.getTarget();
            final BaseStatementHandler delegate = ReflectionUtils.getFieldValue(statementHandler, DELEGATE);
            final MappedStatement mappedStatement = ReflectionUtils.getFieldValue(delegate, MAPPED_STATEMENT);

            //            //?SQL
            ////            if (mappedStatement.getId().matches(_SQL_PATTERN)) { 
            //            if (StringUtils.indexOfIgnoreCase(mappedStatement.getId(), _SQL_PATTERN) != -1) {
            BoundSql boundSql = delegate.getBoundSql();
            //SQL<select>parameterType??Mapper??,??
            Object parameterObject = boundSql.getParameterObject();
            if (parameterObject == null) {
                log.error("?");
                throw new NullPointerException("parameterObject?");
            } else {
                final Connection connection = (Connection) ivk.getArgs()[0];
                final String sql = boundSql.getSql();
                //
                final int count = SQLHelper.getCount(sql, connection, mappedStatement, parameterObject, boundSql,
                        log);
                Page<Object> page = null;
                page = convertParameter(parameterObject, page);
                page.setTotalCount(count);
                String pagingSql = SQLHelper.generatePageSql(sql, page, DIALECT);
                if (log.isDebugEnabled()) {
                    log.debug("PAGE SQL:" + pagingSql);
                }
                //sql???BoundSql.
                ReflectionUtils.setFieldValue(boundSql, "sql", pagingSql);
            }

            if (boundSql.getSql() == null || "".equals(boundSql.getSql())) {
                return null;
            }

        }
        //        }
        return ivk.proceed();
    }

    @Override
    public Object plugin(Object o) {
        return Plugin.wrap(o, this);
    }

    @Override
    public void setProperties(Properties properties) {
        initProperties(properties);
    }
}