kafka自定义序列化器

《kafka权威指南》

Customer.java

public class Customer {
    private int customId;
    private String customerName;

    public Customer(int customId, String customerName) {
        this.customId = customId;
        this.customerName = customerName;
    }

    public int getCustomId() {
        return customId;
    }

    public void setCustomId(int customId) {
        this.customId = customId;
    }

    public String getCustomerName() {
        return customerName;
    }

    public void setCustomerName(String customerName) {
        this.customerName = customerName;
    }
}

CustomerSerializer.java

import org.apache.commons.lang.SerializationException;
import org.apache.kafka.common.serialization.Serializer;

import java.nio.ByteBuffer;
import java.util.Map;

/**
 * 自定义序列化器
 * */
public class CustomerSerializer implements Serializer<Customer> {


    public void configure(Map<String, ?> configs, boolean isKey) {
        //不作任何配置
    }

    /**
     * Customer对象被序列化成:
     * 1. 表示customerId的4字节整数
     * 2. 表示customerName长度的4字节整数（若是customerName为空，则长度为0）
     * 3. 表示customerName的N个字节
     *
     * */
    public byte[] serialize(String topic, Customer data) {
        try{
            byte[] serializedName;
            int stringSize;
            if(data == null)
                return null;
            else{
                if(data.getCustomerName() != null){
                    serializedName = data.getCustomerName().getBytes("UTF-8");
                    stringSize = serializedName.length;

                } //if
                else{
                    serializedName = new byte[0];
                    stringSize = 0;
                }
                ByteBuffer buffer = ByteBuffer.allocate(4 + 4 + stringSize);
                buffer.putInt(data.getCustomId());
                buffer.putInt(stringSize);
                buffer.put(serializedName);
                return buffer.array();
            } //else
        } catch (Exception e){
            e.printStackTrace();
            throw new SerializationException("Error when serizlizing custromer to byte[]" +
            e);
        }
    }

    public void close() {

    }
}