JsonUtil转换成json格式

浏览数：23 / 时间：2015年06月09日

package com.amssy.core.util;

import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
* 转化json数据*
*/
public class JsonUtil {

  /**
*
* @param mapObject map转化list
* @return
*/
public static List changeMapToJsonTypeString(Map mapObject){
  List<Map> thirdLt = new ArrayList<Map>();
  Iterator<Map.Entry> tt = mapObject.entrySet().iterator();
    while (tt.hasNext()) {
     Map testMap = new HashMap();
     Map.Entry entry = tt.next();
     testMap.put("name", entry.getKey());
     testMap.put("value", entry.getValue());
     thirdLt.add(testMap);
  }
  return thirdLt;
}

public static String toJson(final Object o)
    {
        if (o == null)
        {
            return "\"\"";
        }
        if(o instanceof Date){
        return date2JSon(o);
        }
        if(o instanceof Timestamp){
        return timestamp2JSon(o);
        }
        if (o instanceof String ) //String
        {
            return string2Json((String) o);
        }
        if( o instanceof Character){
        return string2Json( String.valueOf(o));
        }
        if (o instanceof Boolean) //Boolean
        {
            return boolean2Json((Boolean) o);
        }
        if (o instanceof BigDecimal) //Boolean
        {
        return bigDecimal2Json((BigDecimal) o);
        }
        if (o instanceof Number) //Number
        {
            return number2Json((Number) o);
        }
        if (o instanceof Map) //Map
        {
            return map2Json((Map<Object, Object>) o);
        }
        if (o instanceof Collection) //List Set
        {
            return collection2Json((Collection) o);
        }
        if (o instanceof Object[]) //对象数组
        {
            return array2Json((Object[]) o);
        }

        if (o instanceof int[])//基本类型数组
        {
            return intArray2Json((int[]) o);
        }
        if (o instanceof boolean[])//基本类型数组
        {
            return booleanArray2Json((boolean[]) o);
        }
        if (o instanceof long[])//基本类型数组
        {
            return longArray2Json((long[]) o);
        }
        if (o instanceof float[])//基本类型数组
        {
            return floatArray2Json((float[]) o);
        }
        if (o instanceof double[])//基本类型数组
        {
            return doubleArray2Json((double[]) o);
        }
        if (o instanceof short[])//基本类型数组
        {
            return shortArray2Json((short[]) o);
        }
        if (o instanceof byte[])//基本类型数组
        {
            return byteArray2Json((byte[]) o);
        }
        if (o instanceof Object) //保底收尾对象
        {
            return object2Json(o);
        }

        throw new RuntimeException("不支持的类型: " + o.getClass().getName());
    }

    private static String bigDecimal2Json(BigDecimal o) {
    o=o.setScale(2, BigDecimal.ROUND_HALF_UP);
    return "\""+String.valueOf(o)+"\"";
}
private static String timestamp2JSon(Object o) {
    if(null==o){
   return "\"\"";
  }
  SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  return "\""+formatter.format(o)+"\"";
}
private static String date2JSon(Object o) {
  if(null==o){
   return "\"\"";
  }
  SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  return "\""+formatter.format(o)+"\"";
}
/**
     * 将 String 对象编码为 JSON格式，只需处理好特殊字符
     *
     * @param s
     *            String 对象
     * @return JSON格式
     */
    static String string2Json(final String s)
    {
        final StringBuilder sb = new StringBuilder();
        sb.append(‘\"‘);
        for (int i = 0; i < s.length(); i++)
        {
            final char c = s.charAt(i);
            switch (c)
            {
            case ‘\"‘:
                sb.append("\\\"");
                break;
            case ‘\\‘:
                sb.append("\\\\");
                break;
            case ‘/‘:
                sb.append("\\/");
                break;
            case ‘\b‘:
                sb.append("\\b");
                break;
            case ‘\f‘:
                sb.append("\\f");
                break;
            case ‘\n‘:
                sb.append("\\n");
                break;
            case ‘\r‘:
                sb.append("\\r");
                break;
            case ‘\t‘:
                sb.append("\\t");
                break;
            default:
                sb.append(c);
            }
        }
        sb.append(‘\"‘);
        return sb.toString();
    }

    /**
     * 将 Number 表示为 JSON格式
     *
     * @param number
     *            Number
     * @return JSON格式
     */
    static String number2Json(final Number number)
    {
        return "\""+number.toString()+"\"";
    }

    /**
     * 将 Boolean 表示为 JSON格式
     *
     * @param bool
     *            Boolean
     * @return JSON格式
     */
    static String boolean2Json(final Boolean bool)
    {
        return "\""+bool.toString()+"\"";
    }

    /**
     * 将 Collection 编码为 JSON 格式 (List,Set)
     *
     * @param c
     * @return
     */
    static String collection2Json(final Collection<Object> c)
    {
        final Object[] arrObj = c.toArray();
        return toJson(arrObj);
    }

    /**
     * 将 Map<String, Object> 编码为 JSON 格式
     *
     * @param map
     * @return
     */
    static String map2Json(final Map<Object, Object> map)
    {
        if (map.isEmpty())
        {
            return "{}";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘{‘);
        final Set<Object> keys = map.keySet();
        for (final Object key : keys)
        {
            final Object value = map.get(key);
            sb.append(‘\"‘);
            sb.append(String.valueOf(key).toUpperCase()); //不能包含特殊字符
            sb.append(‘\"‘);
            sb.append(‘:‘);
            sb.append(toJson(value)); //循环引用的对象会引发无限递归
            sb.append(‘,‘);
        }
        // 将最后的 ‘,‘ 变为 ‘}‘:
        sb.setCharAt(sb.length() - 1, ‘}‘);
        return sb.toString();
    }

    /**
     * 将数组编码为 JSON 格式
     *
     * @param array
     *            数组
     * @return JSON 格式
     */
    static String array2Json(final Object[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final Object o : array)
        {
            sb.append(toJson(o));
            sb.append(‘,‘);
        }
        // 将最后添加的 ‘,‘ 变为 ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String intArray2Json(final int[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final int o : array)
        {
            sb.append("\""+Integer.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String longArray2Json(final long[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final long o : array)
        {
            sb.append("\""+Long.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String booleanArray2Json(final boolean[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final boolean o : array)
        {
            sb.append("\""+Boolean.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String floatArray2Json(final float[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final float o : array)
        {
            sb.append("\""+Float.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String doubleArray2Json(final double[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final double o : array)
        {
            sb.append("\""+Double.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String shortArray2Json(final short[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final short o : array)
        {
            sb.append("\""+Short.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    static String byteArray2Json(final byte[] array)
    {
        if (array.length == 0)
        {
            return "[]";
        }
        final StringBuilder sb = new StringBuilder();
        sb.append(‘[‘);
        for (final byte o : array)
        {
            sb.append("\""+Byte.toString(o)+"\"");
            sb.append(‘,‘);
        }
        // set last ‘,‘ to ‘]‘:
        sb.setCharAt(sb.length() - 1, ‘]‘);
        return sb.toString();
    }

    public static String object2Json(final Object bean)
    {
        //数据检查
        if (bean == null)
        {
            return "{}";
        }
        final Method[] methods = bean.getClass().getMethods(); //方法数组
        final StringBuilder sb = new StringBuilder();
        sb.append(‘{‘);

        for (final Method method : methods)
        {
            try
            {
                final String name = method.getName();
                String key = "";
                if (name.startsWith("get"))
                {
                    key = name.substring(3);

                    //防死循环
                    final String[] arrs =
                    { "Class" };
                    boolean bl = false;
                    for (final String s : arrs)
                    {
                        if (s.equals(key))
                        {
                            bl = true;
                            continue;
                        }
                    }
                    if (bl)
                    {
                        continue; //防死循环
                    }
                }
                else if (name.startsWith("is"))
                {
                    key = name.substring(2);
                }
                if (key.length() > 0 && Character.isUpperCase(key.charAt(0)) && method.getParameterTypes().length == 0)
                {
                    if (key.length() == 1)
                    {
                        key = key.toLowerCase();
                    }
                    else if (!Character.isUpperCase(key.charAt(1)))
                    {
                        key = key.substring(0, 1).toLowerCase() + key.substring(1);
                    }
                    final Object elementObj = method.invoke(bean);

                    //System.out.println("###" + key + ":" + elementObj.toString());

                    sb.append(‘\"‘);
                    sb.append(key.toUpperCase()); //不能包含特殊字符
                    sb.append(‘\"‘);
                    sb.append(‘:‘);
                    sb.append(toJson(elementObj)); //循环引用的对象会引发无限递归
                    sb.append(‘,‘);
                }
            }
            catch (final Exception e)
            {
                //e.getMessage();
                throw new RuntimeException("在将bean封装成JSON格式时异常：" + e.getMessage(), e);
            }
        }
        if (sb.length() == 1)
        {
            return bean.toString();
        }
        else
        {
            sb.setCharAt(sb.length() - 1, ‘}‘);
            return sb.toString();
        }
    }
}