《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) { //不做任何配置 } /** * 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(如果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() { } }