Java tutorial
/* * Copyright 2017 TWO SIGMA OPEN SOURCE, LLC * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.twosigma.beaker.chart.serializer; import com.twosigma.beaker.chart.xychart.plotitem.Rasters; import com.fasterxml.jackson.databind.JsonSerializer; import com.fasterxml.jackson.databind.SerializerProvider; import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.core.JsonProcessingException; import java.io.IOException; import java.io.File; import java.nio.file.Files; import org.apache.commons.codec.binary.Base64; import org.apache.commons.codec.binary.StringUtils; public class RastersSerializer extends JsonSerializer<Rasters> { @Override public void serialize(Rasters raster, JsonGenerator jgen, SerializerProvider sp) throws IOException, JsonProcessingException { jgen.writeStartObject(); jgen.writeObjectField("type", raster.getClass().getSimpleName()); jgen.writeObjectField("x", raster.getX()); jgen.writeObjectField("y", raster.getY()); jgen.writeObjectField("opacity", raster.getOpacity()); jgen.writeObjectField("visible", raster.getVisible()); jgen.writeObjectField("yAxis", raster.getYAxis()); jgen.writeObjectField("position", raster.getPosition()); if (raster.getWidth() != null) { jgen.writeObjectField("width", raster.getWidth()); } if (raster.getHeight() != null) { jgen.writeObjectField("height", raster.getHeight()); } // datastring will override file path/url if (raster.getDataString() != null) { jgen.writeObjectField("value", Bytes2Base64(raster.getDataString(), null)); } else if (!raster.getFilePath().isEmpty()) { String path = raster.getFilePath(); byte[] picture = Files.readAllBytes(new File(path).toPath()); String extension = ""; int i = path.lastIndexOf('.'); if (i > 0) { extension = path.substring(i + 1); } jgen.writeObjectField("value", Bytes2Base64(picture, extension)); } else if (!raster.getFileUrl().isEmpty()) { jgen.writeObjectField("value", raster.getFileUrl()); } jgen.writeEndObject(); } private String processLargeNumber(Number largeNumber) { return largeNumber != null ? largeNumber.toString() : ""; } private String Bytes2Base64(byte[] bytes, String format) { StringBuilder sb = new StringBuilder(); if (format != null) sb.append("data:image/" + format + ";base64,"); else sb.append("data:image/png;base64,"); sb.append(StringUtils.newStringUtf8(Base64.encodeBase64(bytes, false))); return sb.toString(); } }