常用代码

Tools

import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public  class Tools {
    
    private static final Log log = LogFactory.getLog(Tools.class);
    private static ObjectMapper mapper = new ObjectMapper();
    
    static {
        mapper.setSerializationInclusion(Include.NON_NULL);
        mapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
    }
    
    public static String md5(String str) {
        try {  
            MessageDigest md = MessageDigest.getInstance("MD5");  
            md.update(str.getBytes());  
            byte digest[] = md.digest();  
            int i;  
            StringBuffer buf = new StringBuffer("");  
            for (int offset = 0; offset < digest.length; offset++) {  
                i = digest[offset];  
                if (i < 0)  
                    i += 256;  
                if (i < 16)  
                    buf.append("0");  
                buf.append(Integer.toHexString(i));  
            }  
            return buf.toString();  
        } catch (NoSuchAlgorithmException e) {  
            return null;  
        }  
    }
    
    public static String md5(long str) {
        try {  
            MessageDigest md = MessageDigest.getInstance("MD5");  
            md.update((str+"").getBytes());  
            byte digest[] = md.digest();  
            int i;  
            StringBuffer buf = new StringBuffer("");  
            for (int offset = 0; offset < digest.length; offset++) {  
                i = digest[offset];  
                if (i < 0)  
                    i += 256;  
                if (i < 16)  
                    buf.append("0");  
                buf.append(Integer.toHexString(i));  
            }  
            return buf.toString();  
        } catch (NoSuchAlgorithmException e) {  
            return null;  
        }  
    }
    
    public static String write2JsonStr(Object o) {
        String jsonStr = "";
        try {
            jsonStr = mapper.writeValueAsString(o);
        } catch (JsonProcessingException e) {
            log.error("write2JsonStr() exception: " + e.getMessage());
        }
        return jsonStr;
    }

    public static Object json2Object(String json, Class<?> clazz) {
        try {
            return mapper.readValue(json, clazz);
        } catch (JsonParseException e) {
            log.error("json2Object() parseException: " + e.getMessage());
        } catch (JsonMappingException e) {
            log.error("json2Object() mappingException: " + e.getMessage());
        } catch (IOException e) {
            log.error("json2Object() IOException: " + e.getMessage());
        }
        return null;
    }

    public static Map<String, Object> json2Map(String json) {
        try {
            if (StringUtils.isBlank(json)) {
                return new HashMap<String, Object>();
            }
            return mapper.readValue(json, Map.class);
        } catch (JsonParseException e) {
            log.error("json2Map(), 出错的json内容：" + json + " ,JsonParseException: " + e.getMessage());
        } catch (JsonMappingException e) {
            log.error("json2Map(), 出错的json内容：" + json + " ,JsonMappingException: " + e.getMessage());
        } catch (IOException e) {
            log.error("json2Map(), 出错的json内容为：" + json + " ,IOException: " + e.getMessage());
        }
        return new HashMap<String, Object>();
    }

    public static List<Map<String, Object>> jsonArray2List(String jsonArray) {
        try {
            return mapper.readValue(jsonArray, List.class);
        } catch (JsonParseException e) {
            log.error("jsonArray2List() exception, 异常字符串: " + jsonArray, e);
        } catch (JsonMappingException e) {
            log.error("jsonArray2List() exception, 异常字符串: " + jsonArray, e);
        } catch (IOException e) {
            log.error("jsonArray2List() exception", e);
        }
        return new ArrayList<Map<String, Object>>();
    }
    
}