javap命令的使用技巧

package com.thundersoft.metadata.test.kafka;

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.junit.Test;

import java.util.Arrays;
import java.util.Properties;

public class KafkaTest {

 @Test
 public void testProducer() {
 Properties props = new Properties();
 props.put("bootstrap.servers", "192.168.204.30:9092");
 props.put("acks", "all");
 props.put("retries", 0);
 props.put("batch.size", 16384);
 props.put("linger.ms", 1);
 props.put("buffer.memory", 33554432);
 props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
 props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

 Producer<String, String> producer = new KafkaProducer<>(props);
 for(int i = 0; i < 100; i++) {
  producer.send(new ProducerRecord<String, String>("my-topic", Integer.toString(i), Integer.toString(i)));
 }

 producer.close();
 }

 @Test
 public void testKafkaConsumer() {
 Properties props = new Properties();
 props.put("bootstrap.servers", "192.168.204.30:9092");
 props.put("group.id", "test");
 props.put("enable.auto.commit", "true");
 props.put("auto.commit.interval.ms", "1000");
 props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
 props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
 KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
 consumer.subscribe(Arrays.asList("my-topic"));

 while (true) {
  ConsumerRecords<String, String> records = consumer.poll(100);
  for (ConsumerRecord<String, String> record : records)
  System.out.printf("offset = %s, key = %s, value = %s%n", record.topic(), record.key(), record.value());
 }
 }

 public static void main(String[] args) {
 int a = 2;
 int b = 3;
 int sum = a*b;
 System.out.println(sum);
 }

}

public class com.thundersoft.metadata.test.kafka.KafkaTest {
 public com.thundersoft.metadata.test.kafka.KafkaTest();
 public void testProducer();
 public void testKafkaConsumer();
 public static void main(java.lang.String[]);
}

public static void main(String[] args) {
 int a = 2;
 int b = 3;
 int sum = a*b;
 System.out.println(sum);
 }

public static void main(java.lang.String[]);
 Code:
 0: iconst_2
 1: istore_1
 2: iconst_3
 3: istore_2
 4: iload_1
 5: iload_2
 6: imul
 7: istore_3
 8: getstatic #47   // Field java/lang/System.out:Ljava/io/PrintStream;
 11: iload_3
 12: invokevirtual #54   // Method java/io/PrintStream.println:(I)V
 15: return