Java tutorial
/* * Copyright (C) 2011 Openismus GmbH * * This file is part of GWT-Glom. * * GWT-Glom is free software: you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by the * Free Software Foundation, either version 3 of the License, or (at your * option) any later version. * * GWT-Glom is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License * for more details. * * You should have received a copy of the GNU Lesser General Public License * along with GWT-Glom. If not, see <http://www.gnu.org/licenses/>. */ package org.glom.web.server; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import org.apache.commons.lang3.StringUtils; import org.apache.http.client.utils.URIBuilder; import org.glom.web.shared.TypedDataItem; import org.glom.web.shared.libglom.Field.GlomFieldType; import org.glom.web.shared.libglom.layout.LayoutItemField; /** * */ public class Utils { /* * This method safely converts longs from libglom into ints. This method was taken from stackoverflow: * * http://stackoverflow.com/questions/1590831/safely-casting-long-to-int-in-java */ public static int safeLongToInt(final long value) { if (value < Integer.MIN_VALUE || value > Integer.MAX_VALUE) { throw new IllegalArgumentException(value + " cannot be cast to int without changing its value."); } return (int) value; } public static String getFileName(final String fileURI) { final String[] splitURI = fileURI.split(File.separator); return splitURI[splitURI.length - 1]; } static public Object deepCopy(final Object oldObj) { ObjectOutputStream oos = null; ObjectInputStream ois = null; try { final ByteArrayOutputStream bos = new ByteArrayOutputStream(); oos = new ObjectOutputStream(bos); // serialize and pass the object oos.writeObject(oldObj); oos.flush(); final ByteArrayInputStream bin = new ByteArrayInputStream(bos.toByteArray()); ois = new ObjectInputStream(bin); // return the new object return ois.readObject(); } catch (final Exception e) { System.out.println("Exception in deepCopy:" + e); return null; } finally { try { oos.close(); ois.close(); } catch (final IOException e) { System.out.println("Exception in deepCopy during finally: " + e); return null; } } } /** Build the URL for the service that will return the binary data for an image. * * @param primaryKeyValue * @param field * @return */ public static String buildImageDataUrl(final TypedDataItem primaryKeyValue, final String documentID, final String tableName, final LayoutItemField field) { final URIBuilder uriBuilder = buildImageDataUrlStart(documentID, tableName); //TODO: Handle other types: if (primaryKeyValue != null) { uriBuilder.setParameter("value", Double.toString(primaryKeyValue.getNumber())); } uriBuilder.setParameter("field", field.getName()); return uriBuilder.toString(); } /** Build the URL for the service that will return the binary data for an image. * * @param primaryKeyValue * @param field * @return */ public static String buildImageDataUrl(final String documentID, final String tableName, final String layoutName, final int[] path) { final URIBuilder uriBuilder = buildImageDataUrlStart(documentID, tableName); uriBuilder.setParameter("layout", layoutName); uriBuilder.setParameter("layoutpath", buildLayoutPath(path)); return uriBuilder.toString(); } /** * @param documentID * @param tableName * @return */ private static URIBuilder buildImageDataUrlStart(final String documentID, final String tableName) { final URIBuilder uriBuilder = new URIBuilder(); //uriBuilder.setHost(GWT.getModuleBaseURL()); uriBuilder.setPath("OnlineGlom/gwtGlomImages"); //The name of our images servlet. See OnlineGlomImagesServlet. uriBuilder.setParameter("document", documentID); uriBuilder.setParameter("table", tableName); return uriBuilder; } /** Build a :-separated string to represent the path as a string. * @param path * @return */ public static String buildLayoutPath(int[] path) { if ((path == null) || (path.length == 0)) { return null; } String result = new String(); for (int i : path) { if (!result.isEmpty()) { result += ":"; } final String strIndex = Integer.toString(i); result += strIndex; } return result; } /** Get an array of int indices from the :-separated string. * See buildLayoutPath(). * * @param attrLayoutPath * @return The array of indices of the layout items. */ public static int[] parseLayoutPath(final String attrLayoutPath) { if (StringUtils.isEmpty(attrLayoutPath)) { return null; } final String[] strIndices = attrLayoutPath.split(":"); final int[] indices = new int[strIndices.length]; for (int i = 0; i < strIndices.length; ++i) { final String str = strIndices[i]; try { indices[i] = Integer.parseInt(str); } catch (final NumberFormatException nfe) { //TODO: Log the error. return null; } } return indices; } public static void transformUnknownToActualType(final TypedDataItem dataItem, final GlomFieldType actualType) { if (dataItem.getType() == actualType) return; String unknownText = dataItem.getUnknown(); //Avoid repeated checks for null: if (unknownText == null) { unknownText = ""; } switch (actualType) { case TYPE_NUMERIC: // TODO: Is this really locale-independent? double number = 0; if (!StringUtils.isEmpty(unknownText)) { try { number = Double.parseDouble(unknownText); } catch (final NumberFormatException e) { e.printStackTrace(); } } dataItem.setNumber(number); break; case TYPE_TEXT: dataItem.setText(unknownText); break; case TYPE_DATE: final SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd"); Date date = null; try { date = formatter.parse(unknownText); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } dataItem.setDate(date); break; case TYPE_TIME: /*TODO : SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd"); Date date; try { date = formatter.parse(unknownText); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } setDate(date); */ break; case TYPE_BOOLEAN: final boolean bool = unknownText.equals("true"); dataItem.setBoolean(bool); //TODO break; case TYPE_IMAGE: dataItem.setImageDataUrl(unknownText); //setImageData(null);//TODO: Though this is only used for primary keys anyway. break; case TYPE_INVALID: break; default: break; //TODO: Warn because this is unusual? } } }