com.litongjava.db.activerecord.TableBuilder Maven / Gradle / Ivy
package com.litongjava.db.activerecord;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Types;
import java.util.List;
import com.litongjava.model.db.JavaType;
/**
* TableBuilder build the mapping of model between class and table.
*/
public class TableBuilder {
protected JavaType javaType = new JavaType();
public JavaType getJavaType() {
return javaType;
}
public void setJavaType(JavaType javaType) {
this.javaType = javaType;
}
public void build(List tableList, Config config) {
// 支持 useAsDataTransfer(...) 中的 arp.start() 正常运作
if (config.dataSource instanceof NullDataSource) {
return ;
}
Table temp = null;
Connection conn = null;
try {
conn = config.dataSource.getConnection();
TableMapping tableMapping = TableMapping.me();
for (Table table : tableList) {
temp = table;
doBuild(table, conn, config);
tableMapping.putTable(table);
DbKit.addModelToConfigMapping(table.getModelClass(), config);
}
} catch (Exception e) {
if (temp != null) {
System.err.println("Can not create Table object, maybe the table " + temp.getName() + " is not exists.");
}
throw new ActiveRecordException(e);
}
finally {
config.close(conn);
}
}
@SuppressWarnings("unchecked")
protected void doBuild(Table table, Connection conn, Config config) throws SQLException {
table.setColumnTypeMap(config.containerFactory.getAttrsMap());
if (table.getPrimaryKey() == null) {
table.setPrimaryKey(config.dialect.getDefaultPrimaryKey());
}
String sql = config.dialect.forTableBuilderDoBuild(table.getName());
Statement stm = conn.createStatement();
ResultSet rs = stm.executeQuery(sql);
ResultSetMetaData rsmd = rs.getMetaData();
// setColumnType(...) 置入的 java 类型主要用于 core 包下面的 parameter 转成正确的 java 类型
for (int i=1; i<=rsmd.getColumnCount(); i++) {
// 备忘：getColumnName 获取字段真实名称而非 sql as 子句指定的名称
String colName = rsmd.getColumnName(i);
String colClassName = rsmd.getColumnClassName(i);
Class clazz = javaType.getType(colClassName);
if (clazz != null) {
table.setColumnType(colName, clazz);
}
else {
int type = rsmd.getColumnType(i);
if (type == Types.BINARY || type == Types.VARBINARY || type == Types.BLOB) {
table.setColumnType(colName, byte[].class);
}
else if (type == Types.CLOB || type == Types.NCLOB) {
table.setColumnType(colName, String.class);
}
// 支持 oracle.sql.TIMESTAMP
else if (type == Types.TIMESTAMP) {
table.setColumnType(colName, java.sql.Timestamp.class);
}
// 支持 oracle.sql.DATE
// 实际情况是 oracle DATE 字段仍然返回的是 Types.TIMESTAMP，而且 oralce 的 DATE 字段上的 getColumnClassName(i) 方法返回的是 java.sql.Timestamp 可以被正确处理
// 所以，此处的 if 判断一是为了逻辑上的正确性、完备性，二是其它类型的数据库可能用得着
else if (type == Types.DATE) {
table.setColumnType(colName, java.sql.Date.class);
}
// 支持 PostgreSql 的 jsonb json
else if (type == Types.OTHER) {
table.setColumnType(colName, Object.class);
}
else {
table.setColumnType(colName, String.class);
}
// core.TypeConverter
// throw new RuntimeException("You've got new type to mapping. Please add code in " + TableBuilder.class.getName() + ". The ColumnClassName can't be mapped: " + colClassName);
}
}
rs.close();
stm.close();
}
}
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