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There is a newer version: 1.4.7
package com.litongjava.db.activerecord;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.sql.Array;
import java.sql.Blob;
import java.sql.Clob;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Types;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.function.Function;

/**
 * ModelBuilder.
 */
public class ModelBuilder {

  public static final ModelBuilder me = new ModelBuilder();

  @SuppressWarnings({"rawtypes"})
  public  List build(ResultSet rs, Class modelClass) throws SQLException, ReflectiveOperationException {
    return build(rs, modelClass, null);
  }

  @SuppressWarnings({"rawtypes", "unchecked"})
  public  List build(ResultSet rs, Class modelClass, Function func) throws SQLException, ReflectiveOperationException {
    List result = new ArrayList();
    ResultSetMetaData rsmd = rs.getMetaData();
    int columnCount = rsmd.getColumnCount();
    String[] labelNames = new String[columnCount + 1];
    int[] types = new int[columnCount + 1];
    buildLabelNamesAndTypes(rsmd, labelNames, types);
    while (rs.next()) {
      Model ar = modelClass.newInstance();
      Map attrs = ar._getAttrs();
      for (int i = 1; i <= columnCount; i++) {
        Object value;
        if (types[i] < Types.BLOB) {
          value = rs.getObject(i);
        } else {
          if (types[i] == Types.CLOB) {
            value = handleClob(rs.getClob(i));
          } else if (types[i] == Types.NCLOB) {
            value = handleClob(rs.getNClob(i));
          } else if (types[i] == Types.BLOB) {
            value = handleBlob(rs.getBlob(i));
          } else {
            value = rs.getObject(i);
          }
        }

        attrs.put(labelNames[i], value);
      }

      if (func == null) {
        result.add((T) ar);
      } else {
        if (!func.apply((T) ar)) {
          break;
        }
      }
    }
    return result;
  }

  public void buildLabelNamesAndTypes(ResultSetMetaData rsmd, String[] labelNames, int[] types) throws SQLException {
    for (int i = 1; i < labelNames.length; i++) {
      // 备忘：getColumnLabel 获取 sql as 子句指定的名称而非字段真实名称
      labelNames[i] = rsmd.getColumnLabel(i);
      types[i] = rsmd.getColumnType(i);
    }
  }

  public byte[] handleBlob(Blob blob) throws SQLException {
    if (blob == null)
      return null;

    InputStream is = null;
    try {
      is = blob.getBinaryStream();
      if (is == null)
        return null;
      byte[] data = new byte[(int) blob.length()];    // byte[] data = new byte[is.available()];
      if (data.length == 0)
        return null;
      is.read(data);
      return data;
    } catch (IOException e) {
      throw new RuntimeException(e);
    } finally {
      if (is != null)
        try {
          is.close();
        } catch (IOException e) {
          throw new RuntimeException(e);
        }
    }
  }

  public String handleClob(Clob clob) throws SQLException {
    if (clob == null)
      return null;

    Reader reader = null;
    try {
      reader = clob.getCharacterStream();
      if (reader == null)
        return null;
      char[] buffer = new char[(int) clob.length()];
      if (buffer.length == 0)
        return null;
      reader.read(buffer);
      return new String(buffer);
    } catch (IOException e) {
      throw new RuntimeException(e);
    } finally {
      if (reader != null)
        try {
          reader.close();
        } catch (IOException e) {
          throw new RuntimeException(e);
        }
    }
  }


  public Object handleArray(Array array) {
    // 获取数组的 Java 表示形式
    Object arrayObj = null;
    try {
      arrayObj = array.getArray();
    } catch (Exception e) {
      if (e instanceof java.lang.NullPointerException) {
        return null;
      } else {
        e.printStackTrace();
      }
    }
    return arrayObj;
//
//    if (arrayObj != null && arrayObj instanceof Object[]) {
//      Integer[] intArray = Arrays.copyOf((Object[]) arrayObj, ((Object[]) arrayObj).length, Integer[].class);
//
//			return Arrays.stream(intArray).collect(Collectors.toList());
//    }
//
//    return null; // 如果数据无法处理或遇到异常，返回null或相应的错误结果
  }


	
	/* backup before use columnType
	@SuppressWarnings({"rawtypes", "unchecked"})
	static final  List build(ResultSet rs, Class modelClass) throws SQLException, ReflectiveOperationException {
		List result = new ArrayList();
		ResultSetMetaData rsmd = rs.getMetaData();
		int columnCount = rsmd.getColumnCount();
		String[] labelNames = getLabelNames(rsmd, columnCount);
		while (rs.next()) {
			Model ar = modelClass.newInstance();
			Map attrs = ar.getAttrs();
			for (int i=1; i<=columnCount; i++) {
				Object attrValue = rs.getObject(i);
				attrs.put(labelNames[i], attrValue);
			}
			result.add((T)ar);
		}
		return result;
	}
	
	private static final String[] getLabelNames(ResultSetMetaData rsmd, int columnCount) throws SQLException {
		String[] result = new String[columnCount + 1];
		for (int i=1; i<=columnCount; i++)
			result[i] = rsmd.getColumnLabel(i);
		return result;
	}
	*/
	
	/* backup
	@SuppressWarnings({"rawtypes", "unchecked"})
	static final  List build(ResultSet rs, Class modelClass) throws SQLException, ReflectiveOperationException {
		List result = new ArrayList();
		ResultSetMetaData rsmd = rs.getMetaData();
		List labelNames = getLabelNames(rsmd);
		while (rs.next()) {
			Model ar = modelClass.newInstance();
			Map attrs = ar.getAttrs();
			for (String lableName : labelNames) {
				Object attrValue = rs.getObject(lableName);
				attrs.put(lableName, attrValue);
			}
			result.add((T)ar);
		}
		return result;
	}
	
	private static final List getLabelNames(ResultSetMetaData rsmd) throws SQLException {
		int columCount = rsmd.getColumnCount();
		List result = new ArrayList();
		for (int i=1; i<=columCount; i++) {
			result.add(rsmd.getColumnLabel(i));
		}
		return result;
	}
	*/
}