daohelper.java

基于java的组号查询模块

/**
 * 
 */
package com.lily.dap.dao.support;

import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;

import org.apache.commons.lang.StringUtils;

import com.lily.dap.model.QueryExpression;

/**
 * @author zouxuemo
 *
 */
public class DaoHelper {
	private static final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
	
	public static String expressionValue2String(Object value) {
		String v = null;
		if (value == null)
			v = "";
		else if (value instanceof String)
			v = (String)value;
		else if (value instanceof Date)
			v = sdf.format((Date)value);
		else if (value instanceof long[]) {
			long[] ary = (long[])value;
			if (ary.length > 0) {
				StringBuffer sb = new StringBuffer().append(ary[0]);
				
				for (int i = 1; i < ary.length; i++)
					sb.append(QueryExpression.VALUE_SPLIT).append(ary[i]);
				
				v = sb.toString();
			}
		} else if (value instanceof int[]) {
			int[] ary = (int[])value;
			if (ary.length > 0) {
				StringBuffer sb = new StringBuffer().append(ary[0]);
				
				for (int i = 1; i < ary.length; i++)
					sb.append(QueryExpression.VALUE_SPLIT).append(ary[i]);
				
				v = sb.toString();
			}
		} else if (value instanceof Object[]) {
			v = StringUtils.join((Object[])value, QueryExpression.VALUE_SPLIT);
		} else if (value instanceof Collection) {
			Iterator it = ((Collection)value).iterator();
			v = StringUtils.join(it, QueryExpression.VALUE_SPLIT);
		} else	//Long Integer Double Float Boolean
			v = value.toString();
		
		return v;
	}
	
	/** 
	 * 分析数字表达式，并返回其中定义的数字数组<p>
	 * 数字表达式格式为："1-4","1,3,5,7","1-3,5,7-10",其中，1-4表示：1至4，1,3,5,7表示：1 3 5 7
	 *
	 * @param expression 要分析的表达式
	 * @return 返回按照大小排序的整数数组
	 */
	public static int[] parseNumExpression(String expression) {
		if (expression == null || "".equals(expression))
			return new int[0];
		
		int[] temp = new int[1000];
		int ptr = 0;
		String[] tokens = expression.split(",");
		for (int i = 0; i < tokens.length; i++) {
			try {
				int i_val = Integer.parseInt(tokens[i].trim());
				temp[ptr++] = i_val;
			} catch (NumberFormatException e) {
				String[] tmp = tokens[i].split("-");
				if (tmp.length == 2) {
					int bg = 0, ed = 0;
					try {
						bg = Integer.parseInt(tmp[0].trim());
						ed = Integer.parseInt(tmp[1].trim());
					} catch (NumberFormatException e1) {
						continue;
					}
					
					for (int ii = bg; ii <= ed; ii++) {
						temp[ptr++] = ii;
					}
				}
			}
		}
		
		if (ptr == 0)
			return new int[0];
		
		Arrays.sort(temp, 0, ptr);
		int length = 1, old = temp[0];
		for (int i = 1; i < ptr; i++) {
			if (old != temp[i]) {
				length++;
				old = temp[i];
			}
		}
		
		int[] ret = new int[length];
		int index = 0;
		ret[index] = temp[0];
		for (int i = 1; i < ptr; i++) {
			if (ret[index] != temp[i]) 
				ret[++index] = temp[i];
		}
		
		return ret;
	}
	
	public static Method getMethod(Class clazz, String name) throws SecurityException, NoSuchMethodException {
		//如果是boolean的属性，必须用is方法来调用，所以先判断是否有get方法，如果没有，再判断有没有is方法
		Method method = null;
		try {
			method = clazz.getMethod(buildGetMethodName(name), new Class[0]);
		} catch (NoSuchMethodException e) {
			method = clazz.getMethod(buildIsMethodName(name), new Class[0]);
		}
		
		return method;
	}
	
	public static String buildGetMethodName(String str){
		StringBuffer out = new StringBuffer("get");
		out.append(str.substring(0, 1).toUpperCase()).append(str.substring(1));
		return out.toString();
	}
	
	public static String buildIsMethodName(String str){
		StringBuffer out = new StringBuffer("is");
		out.append(str.substring(0, 1).toUpperCase()).append(str.substring(1));
		return out.toString();
	}
}