最近用protobuf来做对象的序列化(不知道我这么表达对不对),用的是百度的jprotobuf,使用注解,当然还有不使用注解的经典方式,本人没用过,发现工作中的竟然在JDK7报错(真怀疑为啥生产用JDK6,现在JDK8了都)只好在github下了最新的,当然google的jar包仍然是必须的
不过有个疑问,protobuf的好处仅仅是为了提供一个兼容跨平台的格式吗,既然最后都是讲对象存为byte[],那直接用流操作使用writeByte(),writeInt(),writeUTf(),写进byte[]里存入文件或数据库有区别么?什么情况下使用protobuf时最佳应用场景?客户端服务器通信?还是其他?
------------------------------------------------------依赖的包---------------------------------------------------------------
jprotobuf-1.2.9.jar
地址点击打开链接
protobuf-0.0.3-beta1.jar
protobuf-java-2.6.1.jar
jprotobuf-1.2.9.jar
---------------------------------------------------------------------------------------------------------------------
package a_serial.protobuf;
import org.apache.commons.lang.builder.ReflectionToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
import com.baidu.bjf.remoting.protobuf.FieldType;
import com.baidu.bjf.remoting.protobuf.annotation.Protobuf;
public class GoodsRecord {
@Protobuf(fieldType = FieldType.INT32, order = 1)
private int goodsId;
@Protobuf(fieldType = FieldType.INT32, order = 2)
private int num;
public GoodsRecord(){
super();
}
public GoodsRecord(int goodsId, int num) {
super();
this.goodsId = goodsId;
this.num = num;
}
/*
* getters and setters
*/
public int getGoodsId() {
return goodsId;
}
public void setGoodsId(int goodsId) {
this.goodsId = goodsId;
}
public int getNum() {
return num;
}
public void setNum(int num) {
this.num = num;
}
@Override
public String toString() {
return ReflectionToStringBuilder.toString(this, ToStringStyle.SHORT_PREFIX_STYLE);
}
}
-----------------------------------------------------------------------------
package a_serial.protobuf;
import java.io.IOException;
import java.util.List;
import org.apache.commons.lang.builder.ReflectionToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
import com.baidu.bjf.remoting.protobuf.Codec;
import com.baidu.bjf.remoting.protobuf.FieldType;
import com.baidu.bjf.remoting.protobuf.ProtobufProxy;
import com.baidu.bjf.remoting.protobuf.annotation.Protobuf;
public class Shop{
@Protobuf(fieldType = FieldType.STRING, order = 1)
private String shopId;
private byte[] data;
@Protobuf(fieldType = FieldType.OBJECT, order = 2)
private List<GoodsRecord> goodsRecordList;
public Shop(){
super();
}
public byte[] getData(){
return data;
}
public String getShopId() {
return shopId;
}
public void setShopId(String shopId) {
this.shopId = shopId;
}
public List<GoodsRecord> getGoodsRecordList() {
return goodsRecordList;
}
public void setGoodsRecordList(List<GoodsRecord> goodsRecordList) {
this.goodsRecordList = goodsRecordList;
}
private Shop parseData(byte[] targetData)
throws IOException {
Codec<Shop> codec = ProtobufProxy.create(Shop.class);
return codec.decode(targetData) ;
}
private byte[] buildData() {
try {
Codec<Shop> codec = ProtobufProxy.create(Shop.class);
return codec.encode(this);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
public void preToData() {
this.data = buildData();
}
public Shop postFromData() {
Shop s = null;
try {
s = parseData(this.data);
this.shopId = s.getShopId();
this.goodsRecordList = s.getGoodsRecordList();
} catch (IOException e) {
e.printStackTrace();
}
return s;
}
public Shop initFromData(byte[] data) {
Shop s = null;
try {
s = parseData(data);
this.shopId = s.getShopId();
this.goodsRecordList = s.getGoodsRecordList();
} catch (IOException e) {
e.printStackTrace();
}
return s;
}
@Override
public String toString() {
return ReflectionToStringBuilder.toString(this, ToStringStyle.SHORT_PREFIX_STYLE);
}
}
-------------------------------------------------------------------------------------------------
package a_serial.protobuf;
import java.io.IOException;
import java.util.ArrayList;
import a_serial.ByteUtil;
import com.google.common.collect.Lists;
/**
* 写
*/
public class ProtoBufTest {
public static void main(String[] args) {
Shop shop = new Shop();
shop.setShopId("10010");
GoodsRecord r = new GoodsRecord(3, 22);
GoodsRecord r2 = new GoodsRecord(4, 22);
ArrayList<GoodsRecord> goodsRecordList = Lists.newArrayList(r, r2);
shop.setGoodsRecordList(goodsRecordList);
shop.preToData();
byte[] data = shop.getData();
try {
ByteUtil.writeFile(data, "protoBuf.os");
} catch (IOException e) {
e.printStackTrace();
}
}
}
--------------------------------------------------------------------------------
package a_serial.protobuf;
import a_serial.ByteUtil;
/**
* 这个是为了读
*/
public class ProtoBufTest2 {
public static void main(String[] args) {
Shop shop = new Shop();
try {
byte[] data = ByteUtil.getData("protoBuf.os");
shop.initFromData(data);
} catch (Exception e) {
e.printStackTrace();
}
System.out.println(shop);
}
}