Activiti工作流资源的获取和存储实现
???? 前两天同事问我，工作流activiti通过activiti-probe部署时候上传的工作流配置文件到存在哪里。我当时懵了，当时知道在数据库存储工作流资源文件的信息。但是不知道文件系统是否存有。于是，研究一下源代码明白，资源信息存储和获取的结构如下：
?在工作流Activiti中流程xml文件和流程图片的存储和实现：
在工作流部署的时候需要上传相关的工作流文件到相关的项目中。其中如果是文件采用方式如下，将图片和或者文件转换为二进制字节流存储。
存储的表结构如下：
create table ACT_GE_BYTEARRAY (
??? ID_ varchar(64) not null,
??? REV_ integer,
??? NAME_ varchar(255),
??? DEPLOYMENT_ID_ varchar(64),
??? BYTES_ BLOB,
??? primary key (ID_)
);
其中NAME_存储文件名称。
??? BYTES_存储流程资源文件。
代码实现如下：
package org.activiti.engine.identity;
?
import java.io.ByteArrayInputStream;
import java.io.InputStream;
?
?
/**
?* @author Tom Baeyens
?*/
public class Picture {
?
? protected byte[] bytes;
? protected String mimeType;
?
? public Picture(byte[] bytes, String mimeType) {
??? this.bytes = bytes;
??? this.mimeType = mimeType;
? }
?
? public byte[] getBytes() {
??? return bytes;
? }
?
? public InputStream getInputStream() {
? ??return new ByteArrayInputStream(bytes);
? }
?
? public String getMimeType() {
??? return mimeType;
? }
}
package org.activiti.rest.api.identity;
?
import org.activiti.engine.ActivitiException;
import org.activiti.engine.identity.Picture;
import org.activiti.rest.api.ActivitiUtil;
import org.activiti.rest.api.SecuredResource;
import org.restlet.data.CacheDirective;
import org.restlet.data.MediaType;
import org.restlet.representation.InputRepresentation;
import org.restlet.resource.Get;
?
/**
?* @author Tijs Rademakers
?*/
public class UserPictureResource extends SecuredResource {
?
? @Get
? public InputRepresentation getPicture() {
??? if(authenticate() == false) return null;
???
??? String userId = (String) getRequest().getAttributes().get("userId");
??? if(userId == null) {
????? throw new ActivitiException("No userId provided");
??? }
??? Picture picture = ActivitiUtil.getIdentityService().getUserPicture(userId);
???
??? String contentType = picture.getMimeType();
??? MediaType mediatType = MediaType.IMAGE_PNG;
??? if(contentType != null) {
????? if(contentType.contains(";")) {
??????? contentType = contentType.substring(0, contentType.indexOf(";"));
????? }
????? mediatType = MediaType.valueOf(contentType);
??? }
??? InputRepresentation output = new InputRepresentation(picture.getInputStream(), mediatType);
??? getResponse().getCacheDirectives().add(CacheDirective.maxAge(28800));
???
??? return output;
? }
?
}
package org.activiti.explorer.util;
?
import java.awt.image.BufferedImage;
?
?
/**
?* @author Joram Barrez
?*/
public class ImageUtil {
?
? protected static final Logger LOGGER = Logger.getLogger(ImageUtil.class.getName());
?
? /**
?? * Resizes the given image (passed as {@link InputStream}.
?? * If the image is smaller then the given maximum width or height, the image
?? * will be proportionally resized.
?? */
? public static InputStream smallify(InputStream imageInputStream, String mimeType, int maxWidth, int maxHeight) {
??? try {
????? BufferedImage image = ImageIO.read(imageInputStream);
?????
???? ?int width = Math.min(image.getWidth(), maxWidth);
????? int height = Math.min(image.getHeight(), maxHeight);
?????
????? Mode mode = Mode.AUTOMATIC;
????? if (image.getHeight() > maxHeight) {
??????? mode = Mode.FIT_TO_HEIGHT;
????? }
?????
????? if (width != image.getWidth() || height != image.getHeight()) {
??????? image = Scalr.resize(image, mode, width, height);
????? }
?????
????? ByteArrayOutputStream bos = new ByteArrayOutputStream();
????? ImageIO.write(image, Constants.MIMETYPE_EXTENSION_MAPPING.get(mimeType), bos);
????? return new ByteArrayInputStream(bos.toByteArray());
??? } catch (IOException e) {
????? LOGGER.log(Level.SEVERE, "Exception while resizing image", e);
????? return null;
??? }
? }
?
}
?
?