package com.iteye.tianshi.core.jdbc;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import java.io.StringWriter;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.lang.StringUtils;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import freemarker.cache.StringTemplateLoader;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;
/**
*
*
* @author jiangzx@yahoo.com
* @Date 2011-6-14 下午01:41:33
*/
public class CustomSQL {
//private static Logger logger = LoggerFactory.getLogger(CustomSQL.class);
private Map<String, SQLBean> _sqlPool;
private static final String GROUP_BY_CLAUSE = " GROUP BY ";
private static final String ORDER_BY_CLAUSE = " ORDER BY ";
private static final String STRING_SPACE = " ";
private final SAXReader saxReader = new SAXReader();
private Configuration configuration = null;
private StringTemplateLoader stringTemplateLoader = null;
public CustomSQL() throws SQLException {
_sqlPool = new HashMap<String, SQLBean>();
try {
ClassLoader classLoader = getClass().getClassLoader();
configuration = new Configuration();
stringTemplateLoader = new StringTemplateLoader();
configuration.setDefaultEncoding("UTF-8");
String[] configs = getConfigs();
for (String _config : configs) {
read(classLoader, _config);
}
configuration.setTemplateLoader(stringTemplateLoader);
}
catch (Exception e) {
//logger.error("", e);
e.printStackTrace();
}
}
protected String[] getConfigs() {
return new String[] {"custom-sql/default.xml"};
}
public String appendCriteria(String sql, String criteria) {
if (StringUtils.isBlank(criteria)) {
return sql;
}
if (!criteria.startsWith(STRING_SPACE)) {
criteria = STRING_SPACE.concat(criteria);
}
if (!criteria.endsWith(STRING_SPACE)) {
criteria = criteria.concat(STRING_SPACE);
}
int pos = sql.indexOf(GROUP_BY_CLAUSE);
if (pos != -1) {
return sql.substring(0, pos + 1).concat(criteria).concat(
sql.substring(pos + 1));
}
pos = sql.indexOf(ORDER_BY_CLAUSE);
if (pos != -1) {
return sql.substring(0, pos + 1).concat(criteria).concat(
sql.substring(pos + 1));
}
return sql.concat(criteria);
}
public String get(String id) {
SQLBean bean = _sqlPool.get(id);
if("simple".equals(bean.getTempateType())) {
return _sqlPool.get(id).getContent();
} else
throw new RuntimeException("SQL 模板类型不正确，只可以是simple类型");
}
public String get(String id, Map<String, Object> model) {
try {
Template template = configuration.getTemplate(id);
StringWriter writer = new StringWriter();
template.process(model, writer);
return writer.toString();
} catch (TemplateException e) {
throw new RuntimeException("Parse sql failed", e);
} catch (IOException e) {
throw new RuntimeException("Parse sql failed", e);
}
}
protected void read(ClassLoader classLoader, String source)
throws Exception {
InputStream is = classLoader.getResourceAsStream(source);
if (is == null) return;
//logger.info("Loading " + source);
Document document = saxReader.read(is);
Element rootElement = document.getRootElement();
for (Object sqlObj : rootElement.elements("sql")) {
Element sqlElement = (Element)sqlObj;
String file = sqlElement.attributeValue("file");
if (StringUtils.isNotBlank(file)) {
read(classLoader, file);
} else {
String id = sqlElement.attributeValue("id");
String sqlType = sqlElement.attributeValue("sqlType");
String templateType = sqlElement.attributeValue("templateType");
if("simple".equals(templateType) || "freeMarker".equals(templateType)) {
String content = transform(sqlElement.getText());
SQLBean bean = new SQLBean();
bean.setTempateType(templateType);
bean.setSqlType(sqlType);
bean.setContent(content);
if("freeMarker".equals(templateType))
stringTemplateLoader.putTemplate(id, content);
_sqlPool.put(id, bean);
} else {
//logger.warn("{} 对应 tempateType 值 {} 不正确，可选值为：simple和freeMarker", id, sqlType);
}
}
}
}
protected String transform(String sql) {
StringBuilder sb = new StringBuilder();
try {
BufferedReader bufferedReader =
new BufferedReader(new StringReader(sql));
String line = null;
while ((line = bufferedReader.readLine()) != null) {
sb.append(line.trim());
sb.append(STRING_SPACE);
}
bufferedReader.close();
}
catch (IOException ioe) {
return sql;
}
return sb.toString();
}
public static class SQLBean {
/**
* 两种可选类型：simple和freeMarker
*/
private String tempateType = "simple";
/**
* 两种可选类型：SQL和HQL
*/
private String sqlType = "SQL";
private String content = "";
public String getTempateType() {
return tempateType;
}
public void setTempateType(String tempateType) {
this.tempateType = tempateType;
}
public String getSqlType() {
return sqlType;
}
public void setSqlType(String sqlType) {
this.sqlType = sqlType;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
}
}