项目总结——java工具类
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目的：
1.抽象公共方法，避免重复造轮子
2.便于统一修改
工具类类型：
1.加载properties配置信息
1）Resource+Spring ClassPathResource
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import java.io.IOException;
import java.util.Properties;
public class DbUtil
private static final Logger logger = LoggerFactory.getLogger(DBConfig.class);
public static final String JDBC_URL = "jdbc.url";
public static final String JDBC_USERNAME ="jdbc.username";
public static final String JDBC_PASSWORD="jdbc.password";
private static final String DB_CONFIG = "db.properties";
private static final Properties properties = new Properties();
static
try
Resource resource = new ClassPathResource(DB_CONFIG);
properties.load(resource.getInputStream());
catch (IOException e)
logger.error("Exception when loading config files", e.getMessage());
public static String getProperties(String key)
return properties.getProperty(key);
2)ResourceBundle
static
ResourceBundle bundle = PropertyResourceBundle.getBundle("db");
ENDPOINT = bundle.containsKey("jdbc.url") == false ? "" : bundle.getString("jdbc.url");
ACCESS_KEY_ID = bundle.containsKey("oss.access.key.id") == false ? "" : bundle.getString("oss.access.key.id");
ACCESS_KEY_SECRET = bundle.containsKey("jdbc.username") == false ? "" : bundle.getString("jdbc.username");
BUCKET_NAME = bundle.containsKey("jdbc.password") == false ? "" : bundle.getString("jdbc.password");
2.文件操作
1)IO流转byte[]数组
public static byte[] toByteArray(InputStream inStream) throws IOException
BufferedInputStream bufferedInputStream = new BufferedInputStream(inStream);
ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
try
byte[] buff = new byte[1024];
int rc = 0;
while ((rc = bufferedInputStream.read(buff)) > 0)
swapStream.write(buff,0,rc);
return swapStream.toByteArray();
catch (Exception e)
logger.error("根据inputStream读取字节异常");
throw new IOException(e.getMessage());
finally
if(swapStream!=null)
swapStream.close();
inStream.close();
2）获取文件扩展名
public static String getExtName(String filename)
if ((filename != null) && (filename.length() > 0))
int dot = filename.lastIndexOf('.');
if ((dot >-1) && (dot < (filename.length() - 1)))
return filename.substring(dot + 1);
return null;
3）获取url网络地址资源的文件size大小
public static long getFileLength(String downloadUrl) throws IOException
if (downloadUrl == null || "".equals(downloadUrl))
return 0L;
URL url = new URL(downloadUrl);
HttpURLConnection conn = null;
try
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows 7; WOW64) AppleWebKit/537.36 (Khtml, like Gecko) Chrome/47.0.2526.73 Safari/537.36 YNoteCef/5.8.0.1 (Windows)");
return (long) conn.getContentLength();
catch (IOException e)
return 0L;
finally
conn.disconnect();
3.分布式主键生成
snowflake算法
public class UUIDUtils
private static IdWorker idWorder;
public UUIDUtils()
public static synchronized long generateId()
return idWorder.nextId();
static
int machineNo = Integer.parseInt(LocalHostUtil.getLastSegment());
idWorder = new IdWorker((long)machineNo);
public class IdWorker
private final long workerId;
private static final long twepoch = 1412092800000L;
private long sequence = 0L;
private static final long workerIdBits = 10L;
private static final long maxWorkerId = 1023L;
private static final long sequenceBits = 12L;
private static final long workerIdShift = 12L;
private static final long timestampLeftShift = 22L;
private static final long sequenceMask = 4095L;
private long lastTimestamp = -1L;
public IdWorker(long workerId)
if(workerId <= 1023L && workerId >= 0L)
this.workerId = workerId;
else
throw new IllegalArgumentException(String.format("worker Id can\\'t be greater than %d or less than 0", new Object[]Long.valueOf(1023L)));
public synchronized long nextId()
long timestamp = this.timeGen();
if(this.lastTimestamp == timestamp)
this.sequence = this.sequence + 1L & 4095L;
if(this.sequence == 0L)
timestamp = this.tilNextMillis(this.lastTimestamp);
else
this.sequence = 0L;
if(timestamp < this.lastTimestamp)
throw new RuntimeException(String.format("Clock moved backwards. Refusing to generate id for %d milliseconds", new Object[]Long.valueOf(this.lastTimestamp - timestamp)));
else
this.lastTimestamp = timestamp;
return timestamp - 1412092800000L << 22 | this.workerId << 12 | this.sequence;
private long tilNextMillis(long lastTimestamp)
long timestamp;
for(timestamp = this.timeGen(); timestamp <= lastTimestamp; timestamp = this.timeGen())
;
return timestamp;
private long timeGen()
return System.currentTimeMillis();
public class LocalHostUtil
private static String localHost = null;
public LocalHostUtil()
public static void setLocalHost(String host)
localHost = host;
public static String getLocalHost() throws Exception
if(isNotBlank(localHost))
return localHost;
else
localHost = findLocalHost();
return localHost;
private static String findLocalHost() throws SocketException, UnknownHostException
Enumeration enumeration = NetworkInterface.getNetworkInterfaces();
InetAddress ipv6Address = null;
while(enumeration.hasMoreElements())
NetworkInterface localHost = (NetworkInterface)enumeration.nextElement();
Enumeration en = localHost.getInetAddresses();
while(en.hasMoreElements())
InetAddress address = (InetAddress)en.nextElement();
if(!address.isLoopbackAddress())
if(!(address instanceof Inet6Address))
return normalizeHostAddress(address);
ipv6Address = address;
if(ipv6Address != null)
return normalizeHostAddress(ipv6Address);
else
InetAddress localHost1 = InetAddress.getLocalHost();
return normalizeHostAddress(localHost1);
private static boolean isNotBlank(String str)
return !isBlank(str);
private static boolean isBlank(String str)
int strLen;
if(str != null && (strLen = str.length()) != 0)
for(int i = 0; i < strLen; ++i)
if(!Character.isWhitespace(str.charAt(i)))
return false;
return true;
else
return true;
public static String normalizeHostAddress(InetAddress localHost)
return localHost instanceof Inet6Address?localHost.getHostAddress():localHost.getHostAddress();
public static String getLastSegment()
try
String e = getLocalHost();
return e.substring(e.lastIndexOf(".") + 1);
catch (Exception var1)
return String.valueOf(System.currentTimeMillis() % 604800000L);
4.Http请求
import java.io.IOException;
import org.apache.http.Consts;
import org.apache.http.HttpEntity;
import org.apache.http.HttpStatus;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;
public class HttpManager
private static final int DEFAULT_CONNECTION_REQUEST_TIMEOUT = 5000;
private static final int DEFAULT_CONNECT_TIMEOUT = 3000;
private static final int DEFAULT_SOCKET_TIMEOUT = 60000;
private static final RequestConfig DEFAULT_REQUEST_CONFIG = RequestConfig.custom()
.setConnectionRequestTimeout(DEFAULT_CONNECTION_REQUEST_TIMEOUT).setConnectTimeout(DEFAULT_CONNECT_TIMEOUT)
.setSocketTimeout(DEFAULT_SOCKET_TIMEOUT).build();
private static final int DEFAULT_FAIL_STATUS = -1;
public static HttpResult<String> post(String uri, RequestBuilder builder)
builder.setUri(uri);
builder.setCharset(Consts.UTF_8);
builder.setConfig(DEFAULT_REQUEST_CONFIG);
CloseableHttpClient client = null;
CloseableHttpResponse response = null;
try
client = HttpClientBuilder.create().setDefaultRequestConfig(DEFAULT_REQUEST_CONFIG)
.build();
response = client.execute(builder.build());
int statusCode = response.getStatusLine().getStatusCode();
String errorMessage = response.getStatusLine().getReasonPhrase();
if (statusCode != HttpStatus.SC_OK)
return HttpResult.fail(statusCode, errorMessage);
HttpEntity responseEntity = response.getEntity();
String content = EntityUtils.toString(responseEntity, Consts.UTF_8);
return HttpResult.success(content);
catch (Exception e)
return HttpResult.fail(DEFAULT_FAIL_STATUS, "请求出错:" + e.getMessage());
finally
if (client != null)
try
client.close();
catch (IOException e)
if (response != null)
try
response.close();
catch (IOException e)
import org.apache.http.HttpStatus;
public class HttpResult<T>
private boolean success;
private int status;
private String message;
private T data;
public static <T> HttpResult<T> success()
return success(null);
public static <T> HttpResult<T> success(T data)
HttpResult<T> result = new HttpResult<>();
result.success = true;
result.status = HttpStatus.SC_OK;
result.data = data;
return result;
public static <T> HttpResult<T> fail(int status, String message)
HttpResult<T> result = new HttpResult<>();
result.success = false;
result.status = status;
result.message = message;
return result;
public boolean isSuccess()
return success;
public void setSuccess(boolean success)
this.success = success;
public int getStatus()
return status;
public void setStatus(int status)
this.status = status;
public String getMessage()
return message;
public void setMessage(String message)
this.message = message;
public T getData()
return data;
public void setData(T data)
this.data = data;
@Override
public String toString()
return "HttpResult" +
"success=" + success +
", status=" + status +
", message='" + message + '\\'' +
", data=" + data +
'';
5.文件处理工具类
1）图片添加水印
public static InputStream getWaterMarkStream(byte[] bytes, String waterMarkMsg,String directionCode)
Color color=new Color(255, 0, 0, 255);//水印颜色
Font font = new Font("微软雅黑", Font.PLAIN, 30); //水印字体
ByteArrayOutputStream outImgStream = null;
try
InputStream origionSteam = new ByteArrayInputStream(bytes);
Image srcImg = ImageIO.read(origionSteam);
int srcImgWidth = srcImg.getWidth(null);
int srcImgHeight = srcImg.getHeight(null);
//加水印
BufferedImage bufImg = new BufferedImage(srcImgWidth, srcImgHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bufImg.createGraphics();
g.drawImage(srcImg, 0, 0, srcImgWidth, srcImgHeight, null);
g.setColor(color);
g.setFont(font);
int x = 0;
int y = 0;
if(directionCode.equals(WaterMarkDirectionEnum.NORTH.getDirectionCode()))
x = (srcImgWidth - g.getFontMetrics(g.getFont()).charsWidth(waterMarkMsg.toCharArray(), 0, waterMarkMsg.length()))/2;
y = srcImgHeight * 2 / 20;
else if (directionCode.equals(WaterMarkDirectionEnum.SOUTH.getDirectionCode()))
x = (srcImgWidth - g.getFontMetrics(g.getFont()).charsWidth(waterMarkMsg.toCharArray(), 0, waterMarkMsg.length())) / 2;
y = srcImgHeight * 18 / 20;
else if (directionCode.equals(WaterMarkDirectionEnum.CENTER.getDirectionCode()))
x = (srcImgWidth - g.getFontMetrics(g.getFont()).charsWidth(waterMarkMsg.toCharArray(), 0, waterMarkMsg.length())) / 2;
y = srcImgHeight / 2;
g.drawString(waterMarkMsg, x, y); //画出水印
g.dispose();
outImgStream = new ByteArrayOutputStream();
ImageIO.write(bufImg, "jpg", outImgStream);
InputStream inputStream = new ByteArrayInputStream(outImgStream.toByteArray());
return inputStream;
catch (IOException e)
throw new SdkException("加水印失败！");
finally
try
outImgStream.close();
catch (IOException e)
e.printStackTrace();
2）graphicsMagick多张图片合成一张图片
import org.im4java.core.*;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.List;
public class ImageUtil
// GraphicsMagick的安装目录，需要在linux上面安装
private static final String GRAPHICS_MAGICK_PATH ;
static
GRAPHICS_MAGICK_PATH = FileConfig.getProperties(FileConfig.GRAPHICS_MAGICK_PATH);
//最大每张图片宽度设置
private static final Integer MAX_WIDTH = 600;
//最大每张图片高度设置
private static final Integer MAX_HEIGHT =400;
/**
* 多张图片合成一张图片
* @param bos 图片信息集合：uuid ,localPicPath图片本地地址
* @param newpath 图片合成后的临时路径
* @param type 1:横,2:竖
*/
public static void montage(List<CoreLocalFileBo> bos , String newpath, String type) throws IOException, IM4JavaException, InterruptedException
Integer maxWidth = MAX_WIDTH;
Integer maxHeight = MAX_HEIGHT;
IMOperation op = new IMOperation();
ConvertCmd cmd = new ConvertCmd(true);
cmd.setSearchPath(GRAPHICS_MAGICK_PATH);
if("1".equals(type))
op.addRawArgs("+append");
else if("2".equals(type))
op.addRawArgs("-append");
op.addRawArgs("-gravity","center");
op.addRawArgs("-bordercolor","#ccc");
op.addRawArgs("-border",1+"x"+1);
op.addRawArgs("-bordercolor","#fff");
for(CoreLocalFileBo coreLocalFileBo : bos)
if(coreLocalFileBo.getFileType().equals("png"))
BufferedImage image = ImageIO.read(new File(coreLocalFileBo .getWholePicPath()));
//获取图片像素点，如果是png格式的，透明的图片，需要转透明图片为白底图片
if((image.getRGB(1,1)>>24)==0)
IMOperation opPngImg = new IMOperation();
ConvertCmd cmdImg = new ConvertCmd(true);
cmdImg.setSearchPath(GRAPHICS_MAGICK_PATH);
opPngImg.addRawArgs("-channel","Opacity");
opPngImg.addImage(coreLocalFileBo.getWholePicPath());
opPngImg.addImage(coreLocalFileBo.getWholePicPath());
cmdImg.run(opPngImg);
opPngImg.dispose();
op.addImage(coreLocalFileBo.getWholePicPath());
else
op.addImage(coreLocalFileBo.getWholePicPath());
else
op.addImage(coreLocalFileBo.getWholePicPath());
if("0".equals(type))
Integer whole_width = (1 + maxWidth +1)* bos.size() ;
Integer whole_height = maxHeight + 1;
op.addRawArgs("-extent",whole_width + "x" +whole_height);
else if("1".equals(type))
Integer whole_width = maxWidth + 1;
Integer whole_height = ( +1 + maxHeight + +1)* bos.size() ;
op.addRawArgs("-extent",whole_width + "x" +whole_height);
op.addImage(newpath);
try
cmd.run(op);
catch (Exception e)
e.printStackTrace();
finally
op.dispose();
3）pdf合成
import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import com.itextpdf.text.*;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.PdfWriter;
import org.slf4j.LoggerFactory;
public ByteArrayOutputStream createPdf(Map<String , byte[]> downlodFileMap ,List<WaterMarkDto> waterMarkDtos ) throws Exception
Document document = new Document(PageSize.A4, 10, 10, 10, 10);
PdfWriter pdfWriter = null;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
try
pdfWriter = PdfWriter.getInstance(document, bos);
pdfWriter.setViewerPreferences(PdfWriter.PageLayoutOneColumn);// 设置文档单页显示
document.open();
byte[] ZERO = new byte[0];
for (WaterMarkDto dto : waterMarkDtos)
if(Arrays.equals(downlodFileMap .get(dto.getUuid()),ZERO) )
continue;
Image image = Image.getInstance(downlodFileMap .get(dto.getUuid()));
image.setAlignment(Image.ALIGN_CENTER); // 居中显示 Image.ALIGN_CENTER
float imgWidth = image.getWidth();// 获取图片宽度
float imgHeight = image.getHeight();// 获取图片高度
if (imgWidth > imgHeight)
document.setPageSize(PageSize.A4.rotate());
else
document.setPageSize(PageSize.A4);
document.newPage();
float width = document.getPageSize().getWidth() - 30;// 取页面宽度并减去页边距
float height = document.getPageSize().getHeight() - 40;// 取页面高度并减去页边距
image.scalePercent(width / imgWidth * 100, height / imgHeight * 100);
String waterMsg = dto.getWaterMarkMessage();
if(waterMsg.getBytes().length > 78)
logger.info("waterMarkMessage原始长度为，太长截取部分",dto.getWaterMarkMessage().getBytes().length );
waterMsg = waterMsg.substring(0,26);
Chunk chunk = new Chunk(waterMsg);
BaseFont bfChinese = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
Font font = new Font(bfChinese, 22, Font.NORMAL, new BaseColor(255, 0, 0));
chunk.setFont(font);
Paragraph paragraph = new Paragraph();
paragraph.add(chunk);
document.add(paragraph);
document.add(image);
document.addCreator("dragon");
catch(Exception e)
e.printStackTrace();
finally
document.close();
pdfWriter.close();
return bos;
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