Java开发工具类集合

Java开发工具类集合

01、MD5加密工具类

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public final class MD5 {

    public static String encrypt(String strSrc) {
        try {
            char hexChars[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8',
                    '9', 'a', 'b', 'c', 'd', 'e', 'f' };
            byte[] bytes = strSrc.getBytes();
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(bytes);
            bytes = md.digest();
            int j = bytes.length;
            char[] chars = new char[j * 2];
            int k = 0;
            for (int i = 0; i < bytes.length; i++) {
                byte b = bytes[i];
                chars[k++] = hexChars[b >>> 4 & 0xf];
                chars[k++] = hexChars[b & 0xf];
            }
            return new String(chars);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            throw new RuntimeException("MD5加密出错！！+" + e);
        }
    }

    public static void main(String[] args) {
        System.out.println(MD5.encrypt("111111"));
    }

}

02、手机号码校验工具类

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 校验手机号码
 */
public class FormUtils {

    /**
     * 手机号验证
     */
    public static boolean isMobile(String str) {
        Pattern p = Pattern.compile("^[1][3,4,5,7,8,9][0-9]{9}$"); // 验证手机号
        Matcher m = p.matcher(str);
        return m.matches();
    }

}

03、验证码生成工具类

import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Random;

/**
 * 获取随机数
 */
public class RandomUtils {

	private static final Random random = new Random();

	private static final DecimalFormat fourdf = new DecimalFormat("0000");

	private static final DecimalFormat sixdf = new DecimalFormat("000000");

	public static String getFourBitRandom() {
		return fourdf.format(random.nextInt(10000));
	}

	public static String getSixBitRandom() {
		return sixdf.format(random.nextInt(1000000));
	}

	/**
	 * 给定数组，抽取n个数据
	 * @param list
	 * @param n
	 * @return
	 */
	public static ArrayList getRandom(List list, int n) {

		Random random = new Random();
		HashMap<Object, Object> hashMap = new HashMap<Object, Object>();

		// 生成随机数字并存入HashMap
		for (int i = 0; i < list.size(); i++) {
			int number = random.nextInt(100) + 1;
			hashMap.put(number, i);
		}

		// 从HashMap导入数组
		Object[] robjs = hashMap.values().toArray();
		ArrayList r = new ArrayList();
		// 遍历数组并打印数据
		for (int i = 0; i < n; i++) {
			r.add(list.get((int) robjs[i]));
			System.out.print(list.get((int) robjs[i]) + "\t");
		}
		System.out.print("\n");
		return r;
	}
}

04、InputStream流转换成String字符串

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class StreamUtils {

    private static int _buffer_size = 1024;

    /**
     * InputStream流转换成String字符串
     * @param inStream InputStream流
     * @param encoding 编码格式
     * @return String字符串
     */
    public static String inputStream2String(InputStream inStream, String encoding){
        String result = null;
        ByteArrayOutputStream outStream = null;
        try {
            if(inStream != null){
                outStream = new ByteArrayOutputStream();
                byte[] tempBytes = new byte[_buffer_size];
                int count = -1;
                while((count = inStream.read(tempBytes, 0, _buffer_size)) != -1){
                    outStream.write(tempBytes, 0, count);
                }
                tempBytes = null;
                outStream.flush();
                result = new String(outStream.toByteArray(), encoding);

                outStream.close();
            }
        } catch (Exception e) {
            result = null;
        } finally {
            try {
                if(inStream != null) {
                    inStream.close();
                    inStream = null;
                }
                if(outStream != null) {
                    outStream.close();
                    outStream = null;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }
}

05、商品订单号生成工具类

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;

/**
 * 订单号工具类
 *
 * @author qy
 * @since 1.0
 */
public class OrderNoUtils {

    /**
     * 获取订单号
     * @return
     */
    public static String getOrderNo() {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
        String newDate = sdf.format(new Date());
        String result = "";
        Random random = new Random();
        for (int i = 0; i < 3; i++) {
            result += random.nextInt(10);
        }
        return newDate + result;
    }

}

06、异常信息获取工具类

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;

/**
 * 获取异常信息
 */
public class ExceptionUtils {

    public static String getMessage(Exception e) {
        StringWriter sw = null;
        PrintWriter pw = null;
        try {
            sw = new StringWriter();
            pw = new PrintWriter(sw);
            // 将出错的栈信息输出到printWriter中
            e.printStackTrace(pw);
            pw.flush();
            sw.flush();
        } finally {
            if (sw != null) {
                try {
                    sw.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
            if (pw != null) {
                pw.close();
            }
        }
        return sw.toString();
    }
}

07、httpClient工具类(需要先引入HttpClient依赖)

<dependencies>
    <!--微信支付-->
    <dependency>
        <groupId>com.github.wxpay</groupId>
        <artifactId>wxpay-sdk</artifactId>
        <version>0.0.3</version>
    </dependency>
</dependencies>

/**
 * http请求客户端
 */
public class HttpClientUtils {
	private String url;
	private Map<String, String> param;
	private int statusCode;
	private String content;
	private String xmlParam;
	private boolean isHttps;

	public boolean isHttps() {
		return isHttps;
	}

	public void setHttps(boolean isHttps) {
		this.isHttps = isHttps;
	}

	public String getXmlParam() {
		return xmlParam;
	}

	public void setXmlParam(String xmlParam) {
		this.xmlParam = xmlParam;
	}

	public HttpClientUtils(String url, Map<String, String> param) {
		this.url = url;
		this.param = param;
	}

	public HttpClientUtils(String url) {
		this.url = url;
	}

	public void setParameter(Map<String, String> map) {
		param = map;
	}

	public void addParameter(String key, String value) {
		if (param == null)
			param = new HashMap<String, String>();
		param.put(key, value);
	}

	public void post() throws ClientProtocolException, IOException {
		HttpPost http = new HttpPost(url);
		setEntity(http);
		execute(http);
	}

	public void put() throws ClientProtocolException, IOException {
		HttpPut http = new HttpPut(url);
		setEntity(http);
		execute(http);
	}

	public void get() throws ClientProtocolException, IOException {
		if (param != null) {
			StringBuilder url = new StringBuilder(this.url);
			boolean isFirst = true;
			for (String key : param.keySet()) {
				if (isFirst) {
					url.append("?");
					isFirst = false;
				}else {
					url.append("&");
				}
				url.append(key).append("=").append(param.get(key));
			}
			this.url = url.toString();
		}
		HttpGet http = new HttpGet(url);
		execute(http);
	}

	/**
	 * set http post,put param
	 */
	private void setEntity(HttpEntityEnclosingRequestBase http) {
		if (param != null) {
			List<NameValuePair> nvps = new LinkedList<NameValuePair>();
			for (String key : param.keySet())
				nvps.add(new BasicNameValuePair(key, param.get(key))); // 参数
			http.setEntity(new UrlEncodedFormEntity(nvps, Consts.UTF_8)); // 设置参数
		}
		if (xmlParam != null) {
			http.setEntity(new StringEntity(xmlParam, Consts.UTF_8));
		}
	}

	private void execute(HttpUriRequest http) throws ClientProtocolException,
			IOException {
		CloseableHttpClient httpClient = null;
		try {
			if (isHttps) {
				SSLContext sslContext = new SSLContextBuilder()
						.loadTrustMaterial(null, new TrustStrategy() {
							// 信任所有
							public boolean isTrusted(X509Certificate[] chain,
									String authType)
									throws CertificateException {
								return true;
							}
						}).build();
				SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(
						sslContext);
				httpClient = HttpClients.custom().setSSLSocketFactory(sslsf)
						.build();
			} else {
				httpClient = HttpClients.createDefault();
			}
			CloseableHttpResponse response = httpClient.execute(http);
			try {
				if (response != null) {
					if (response.getStatusLine() != null)
						statusCode = response.getStatusLine().getStatusCode();
					HttpEntity entity = response.getEntity();
					// 响应内容
					content = EntityUtils.toString(entity, Consts.UTF_8);
				}
			} finally {
				response.close();
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			httpClient.close();
		}
	}

	public int getStatusCode() {
		return statusCode;
	}

	public String getContent() throws ParseException, IOException {
		return content;
	}

}

08、JWT工具类

public class JwtUtils {

    public static final String APP_SECRET = "ukc8BDbRigUDaY6pZFfWus2jZWLPHO";

    private static Key getKeyInstance(){
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;
        byte[] bytes = DatatypeConverter.parseBase64Binary(APP_SECRET);
        return new SecretKeySpec(bytes,signatureAlgorithm.getJcaName());
    }

    public static String getJwtToken(JwtInfo jwtInfo, int expire){

        String JwtToken = Jwts.builder()
                .setHeaderParam("typ", "JWT")
                .setHeaderParam("alg", "HS256")
                .setSubject("guli-user")//主题
                .setIssuedAt(new Date())//颁发时间
                .setExpiration(DateTime.now().plusSeconds(expire).toDate())//过期时间
                .claim("id", jwtInfo.getId())//用户id
                .claim("nickname", jwtInfo.getNickname())//用户昵称
                .claim("avatar", jwtInfo.getAvatar())//用户头像
                .signWith(SignatureAlgorithm.HS256, getKeyInstance())
                .compact();

        return JwtToken;
    }

    /**
     * 判断token是否存在与有效
     * @param jwtToken
     * @return
     */
    public static boolean checkJwtTToken(String jwtToken) {
        if(StringUtils.isEmpty(jwtToken)) return false;
        try {
            Jwts.parser().setSigningKey(getKeyInstance()).parseClaimsJws(jwtToken);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }

    /**
     * 判断token是否存在与有效
     * @param request
     * @return
     */
    public static boolean checkJwtTToken(HttpServletRequest request) {
        try {
            String jwtToken = request.getHeader("token");
            if(StringUtils.isEmpty(jwtToken)) return false;
            Jwts.parser().setSigningKey(getKeyInstance()).parseClaimsJws(jwtToken);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }

    /**
     * 根据token获取会员id
     * @param request
     * @return
     */
    public static JwtInfo getMemberIdByJwtToken(HttpServletRequest request) {
        String jwtToken = request.getHeader("token");
        if(StringUtils.isEmpty(jwtToken)) return null;
        Jws<Claims> claimsJws = Jwts.parser().setSigningKey(getKeyInstance()).parseClaimsJws(jwtToken);
        Claims claims = claimsJws.getBody();
        JwtInfo jwtInfo = new JwtInfo(claims.get("id").toString(), claims.get("nickname").toString(), claims.get("avatar").toString());
        return jwtInfo;
    }
}

09、cookie工具类

public final class CookieUtils {
    /**
     * 得到Cookie的值, 不编码
     *
     * @param request
     * @param cookieName
     * @return
     */
    public static String getCookieValue(HttpServletRequest request, String cookieName) {
        return getCookieValue(request, cookieName, false);
    }

    /**
     * 得到Cookie的值,
     *
     * @param request
     * @param cookieName
     * @return
     */
    public static String getCookieValue(HttpServletRequest request, String cookieName, boolean isDecoder) {
        Cookie[] cookieList = request.getCookies();
        if (cookieList == null || cookieName == null) {
            return null;
        }
        String retValue = null;
        try {
            for (int i = 0; i < cookieList.length; i++) {
                if (cookieList[i].getName().equals(cookieName)) {
                    if (isDecoder) {
                        retValue = URLDecoder.decode(cookieList[i].getValue(), "UTF-8");
                    } else {
                        retValue = cookieList[i].getValue();
                    }
                    break;
                }
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return retValue;
    }

    /**
     * 得到Cookie的值,
     *
     * @param request
     * @param cookieName
     * @return
     */
    public static String getCookieValue(HttpServletRequest request, String cookieName, String encodeString) {
        Cookie[] cookieList = request.getCookies();
        if (cookieList == null || cookieName == null) {
            return null;
        }
        String retValue = null;
        try {
            for (int i = 0; i < cookieList.length; i++) {
                if (cookieList[i].getName().equals(cookieName)) {
                    retValue = URLDecoder.decode(cookieList[i].getValue(), encodeString);
                    break;
                }
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return retValue;
    }

    /**
     * 设置Cookie的值 不设置生效时间默认浏览器关闭即失效,也不编码
     */
    public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
                                 String cookieValue) {
        setCookie(request, response, cookieName, cookieValue, -1);
    }

    /**
     * 设置Cookie的值 在指定时间内生效,但不编码
     */
    public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
                                 String cookieValue, int cookieMaxage) {
        setCookie(request, response, cookieName, cookieValue, cookieMaxage, false);
    }

    /**
     * 设置Cookie的值 不设置生效时间,但编码
     */
    public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
                                 String cookieValue, boolean isEncode) {
        setCookie(request, response, cookieName, cookieValue, -1, isEncode);
    }

    /**
     * 设置Cookie的值 在指定时间内生效, 编码参数
     */
    public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
                                 String cookieValue, int cookieMaxage, boolean isEncode) {
        doSetCookie(request, response, cookieName, cookieValue, cookieMaxage, isEncode);
    }

    /**
     * 设置Cookie的值 在指定时间内生效, 编码参数(指定编码)
     */
    public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
                                 String cookieValue, int cookieMaxage, String encodeString) {
        doSetCookie(request, response, cookieName, cookieValue, cookieMaxage, encodeString);
    }

    /**
     * 删除Cookie带cookie域名
     */
    public static void deleteCookie(HttpServletRequest request, HttpServletResponse response,
                                    String cookieName) {
        doSetCookie(request, response, cookieName, "", -1, false);
    }

    /**
     * 设置Cookie的值，并使其在指定时间内生效
     *
     * @param cookieMaxage cookie生效的最大秒数
     */
    private static final void doSetCookie(HttpServletRequest request, HttpServletResponse response,
                                          String cookieName, String cookieValue, int cookieMaxage, boolean isEncode) {
        try {
            if (cookieValue == null) {
                cookieValue = "";
            } else if (isEncode) {
                cookieValue = URLEncoder.encode(cookieValue, "utf-8");
            }
            Cookie cookie = new Cookie(cookieName, cookieValue);
            if (cookieMaxage > 0)
                cookie.setMaxAge(cookieMaxage);
            if (null != request) {// 设置域名的cookie
                String domainName = getDomainName(request);
//                System.out.println(domainName);
                if (!"localhost".equals(domainName)) {
                    cookie.setDomain(domainName);
                }
            }
            cookie.setPath("/");
            response.addCookie(cookie);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 设置Cookie的值，并使其在指定时间内生效
     *
     * @param cookieMaxage cookie生效的最大秒数
     */
    private static final void doSetCookie(HttpServletRequest request, HttpServletResponse response,
                                          String cookieName, String cookieValue, int cookieMaxage, String encodeString) {
        try {
            if (cookieValue == null) {
                cookieValue = "";
            } else {
                cookieValue = URLEncoder.encode(cookieValue, encodeString);
            }
            Cookie cookie = new Cookie(cookieName, cookieValue);
            if (cookieMaxage > 0)
                cookie.setMaxAge(cookieMaxage);
            if (null != request) {// 设置域名的cookie
                String domainName = getDomainName(request);
//                System.out.println(domainName);
                if (!"localhost".equals(domainName)) {
                    cookie.setDomain(domainName);
                }
            }
            cookie.setPath("/");
            response.addCookie(cookie);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 得到cookie的域名
     */
    private static final String getDomainName(HttpServletRequest request) {
        String domainName = null;

        String serverName = request.getRequestURL().toString();
        if (serverName == null || serverName.equals("")) {
            domainName = "";
        } else {
            serverName = serverName.toLowerCase();
            serverName = serverName.substring(7);
            final int end = serverName.indexOf("/");
            serverName = serverName.substring(0, end);
            final String[] domains = serverName.split("\\.");
            int len = domains.length;
            if (len > 3) {
                // www.xxx.com.cn
                domainName = "." + domains[len - 3] + "." + domains[len - 2] + "." + domains[len - 1];
            } else if (len <= 3 && len > 1) {
                // xxx.com or xxx.cn
                domainName = "." + domains[len - 2] + "." + domains[len - 1];
            } else {
                domainName = serverName;
            }
        }

        if (domainName != null && domainName.indexOf(":") > 0) {
            String[] ary = domainName.split("\\:");
            domainName = ary[0];
        }
        return domainName;
    }
}

10、Base64工具类

/**
 * Base64 工具类
 */
public class Base64Util {
    private static final char last2byte = (char) Integer.parseInt("00000011", 2);
    private static final char last4byte = (char) Integer.parseInt("00001111", 2);
    private static final char last6byte = (char) Integer.parseInt("00111111", 2);
    private static final char lead6byte = (char) Integer.parseInt("11111100", 2);
    private static final char lead4byte = (char) Integer.parseInt("11110000", 2);
    private static final char lead2byte = (char) Integer.parseInt("11000000", 2);
    private static final char[] encodeTable = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};

    public Base64Util() {
    }

    public static String encode(byte[] from) {
        StringBuilder to = new StringBuilder((int) ((double) from.length * 1.34D) + 3);
        int num = 0;
        char currentByte = 0;

        int i;
        for (i = 0; i < from.length; ++i) {
            for (num %= 8; num < 8; num += 6) {
                switch (num) {
                    case 0:
                        currentByte = (char) (from[i] & lead6byte);
                        currentByte = (char) (currentByte >>> 2);
                    case 1:
                    case 3:
                    case 5:
                    default:
                        break;
                    case 2:
                        currentByte = (char) (from[i] & last6byte);
                        break;
                    case 4:
                        currentByte = (char) (from[i] & last4byte);
                        currentByte = (char) (currentByte << 2);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead2byte) >>> 6);
                        }
                        break;
                    case 6:
                        currentByte = (char) (from[i] & last2byte);
                        currentByte = (char) (currentByte << 4);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead4byte) >>> 4);
                        }
                }

                to.append(encodeTable[currentByte]);
            }
        }

        if (to.length() % 4 != 0) {
            for (i = 4 - to.length() % 4; i > 0; --i) {
                to.append("=");
            }
        }

        return to.toString();
    }
}

11、文件读取工具类

import java.io.*;

/**
 * 文件读取工具类
 */
public class FileUtil {

    /**
     * 读取文件内容，作为字符串返回
     */
    public static String readFileAsString(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            throw new FileNotFoundException(filePath);
        } 

        if (file.length() > 1024 * 1024 * 1024) {
            throw new IOException("File is too large");
        } 

        StringBuilder sb = new StringBuilder((int) (file.length()));
        // 创建字节输入流
        FileInputStream fis = new FileInputStream(filePath);
        // 创建一个长度为10240的Buffer
        byte[] bbuf = new byte[10240];
        // 用于保存实际读取的字节数
        int hasRead = 0;
        while ( (hasRead = fis.read(bbuf)) > 0 ) {
            sb.append(new String(bbuf, 0, hasRead));
        }
        fis.close();
        return sb.toString();
    }

    /**
     * 根据文件路径读取byte[] 数组
     */
    public static byte[] readFileByBytes(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            throw new FileNotFoundException(filePath);
        } else {
            ByteArrayOutputStream bos = new ByteArrayOutputStream((int) file.length());
            BufferedInputStream in = null;

            try {
                in = new BufferedInputStream(new FileInputStream(file));
                short bufSize = 1024;
                byte[] buffer = new byte[bufSize];
                int len1;
                while (-1 != (len1 = in.read(buffer, 0, bufSize))) {
                    bos.write(buffer, 0, len1);
                }

                byte[] var7 = bos.toByteArray();
                return var7;
            } finally {
                try {
                    if (in != null) {
                        in.close();
                    }
                } catch (IOException var14) {
                    var14.printStackTrace();
                }

                bos.close();
            }
        }
    }
}