Java tutorial
package org.eluder.logback.ext.jackson; /* * #[license] * logback-ext-jackson * %% * Copyright (C) 2014 - 2015 Tapio Rautonen * %% * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * %[license] */ import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.core.util.MinimalPrettyPrinter; import com.fasterxml.jackson.databind.ObjectMapper; import java.io.Closeable; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.nio.charset.Charset; public class JsonWriter implements Closeable { private final JsonGenerator generator; public JsonWriter(OutputStream os, Charset charset, ObjectMapper mapper) throws IOException { generator = mapper.getFactory().createGenerator(new OutputStreamWriter(os, charset)) .configure(JsonGenerator.Feature.AUTO_CLOSE_TARGET, false) .setPrettyPrinter(new MinimalPrettyPrinter("")); } @Override public void close() throws IOException { generator.close(); } public JsonWriter flush() throws IOException { generator.flush(); return this; } public JsonWriter newline() throws IOException { generator.writeRaw('\n'); return this; } public ObjectWriter<JsonWriter> writeObject() throws IOException { return new ObjectWriter<JsonWriter>(this, true); } public ArrayWriter<JsonWriter> writeArray() throws IOException { return new ArrayWriter<JsonWriter>(this, true); } public class ObjectWriter<T> { private final T parent; private final boolean enabled; ObjectWriter(T parent, boolean parentEnabled) throws IOException { this.parent = parent; this.enabled = parentEnabled; if (enabled) { generator.writeStartObject(); } } ObjectWriter(T parent, boolean parentEnabled, String name, boolean active) throws IOException { this.parent = parent; this.enabled = parentEnabled && active; if (enabled) { generator.writeObjectFieldStart(name); } } public ObjectWriter<T> writeStringField(String name, String value, boolean active) throws IOException { if (enabled && active) { generator.writeStringField(name, value); } return this; } public ObjectWriter<T> writeNumberField(String name, int value, boolean active) throws IOException { if (enabled && active) { generator.writeNumberField(name, value); } return this; } public ObjectWriter<T> writeNumberField(String name, long value, boolean active) throws IOException { if (enabled && active) { generator.writeNumberField(name, value); } return this; } public ArrayWriter<ObjectWriter<T>> writeArray(String name, boolean active) throws IOException { return new ArrayWriter<ObjectWriter<T>>(this, enabled, name, active); } public ObjectWriter<ObjectWriter<T>> writeObject(String name, boolean active) throws IOException { return new ObjectWriter<ObjectWriter<T>>(this, enabled, name, active); } public T done() throws IOException { if (enabled) { generator.writeEndObject(); } return parent; } } public class ArrayWriter<T> { private final T parent; private final boolean enabled; ArrayWriter(T parent, boolean parentEnabled) throws IOException { this.parent = parent; this.enabled = parentEnabled; if (enabled) { generator.writeStartArray(); } } ArrayWriter(T parent, boolean parentEnabled, String name, boolean active) throws IOException { this.parent = parent; this.enabled = parentEnabled && active; if (enabled) { generator.writeArrayFieldStart(name); } } public ArrayWriter<T> writeString(String value, boolean active) throws IOException { if (enabled && active) { generator.writeString(value); } return this; } public ArrayWriter<ArrayWriter<T>> writeArray() throws IOException { return new ArrayWriter<ArrayWriter<T>>(this, enabled); } public ObjectWriter<ArrayWriter<T>> writeObject() throws IOException { return new ObjectWriter<ArrayWriter<T>>(this, enabled); } public T done() throws IOException { if (enabled) { generator.writeEndArray(); } return parent; } } }