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package com.gem.demo.java;

import java.util.NoSuchElementException;
import java.util.Random;

public class RandomString {
    public static void main(String[] args) {
        long time = System.currentTimeMillis();
        generate("hello");
        generate("world");

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Arrays.stream(TimeZone.getAvailableIDs()).forEach(id -> {
  boolean flag = false;
  try {
    ZoneId.of(id);
    flag = true;
  } catch (Exception e) {
    //ignore;
  }
  if (!flag)
    System.out.printf("[%s] %s%n", flag ? "x" : " ", id);

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@Entity
public class Employee extends AbstractBaseEntity {
  //  Approach 1:
  //  @Id
  //  public String id;

  //  Approach 2:
  @Id
  // default column type is byte array
  @Type(type = "org.hibernate.type.PostgresUUIDType") // or type = "pg-uuid"

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interface NoArgConstructor<T> {
    T foo();
}

interface ArgConstructor<T, U> {
    T bar(U arg);
}

interface MultiArgsConstructor<T, U> {
    T magic(U... arg);

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package com.gem.demo.database.model;

public class Company {
    public int id;
    public String name;
    public String address;

    ...

    @Override

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[EL Info]: connection: 2015-08-30 12:52:11.554--ServerSession(1286783232)--/file:/C:/Users/KiT/IdeaProjects/Database Sample/service/target/classes/_pu login successful
Employee.prePersist
[EL Fine]: sql: 2015-08-30 12:52:11.635--ClientSession(1437983537)--Connection(1614079837)--INSERT INTO EMPLOYEE (NAME, SALARY) VALUES (?, ?)
	bind => [2 parameters bound]
[EL Fine]: sql: 2015-08-30 12:52:11.637--ClientSession(1437983537)--Connection(1614079837)--SELECT LAST_INSERT_ID()
Employee.postPersist
========================================
[EL Fine]: sql: 2015-08-30 12:52:11.729--ServerSession(1286783232)--Connection(1614079837)--SELECT ID, NAME, SALARY FROM EMPLOYEE WHERE (ID = ?)
	bind => [1 parameter bound]
Employee.postLoad

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import javax.persistence.*;

@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    private String name;
    @Lob
    private String avatar;

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...
[EL Fine]: sql: 2015-08-30 10:11:24.497--ServerSession(1622006612)--Connection(530410619)--SELECT ID, NAME, SALARY FROM EMPLOYEE WHERE (ID = ?)
	bind => [1 parameter bound]
Employee.setName(KiT)     // when manager.find(Employee.class, id);
Employee.getName() => KiT
Employee.setName(KiT)
Employee.getName() => KiT
Employee.setName(KiT)
Employee #1: KiT (12345)
Employee.getName() => KiT // when transaction.commit();

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// JPA defines named parameters, and positional parameters.

// Named parameters can be specified in JPQL using the syntax :<name>.
Query query = em.createQuery("SELECT e FROM Employee e WHERE e.firstName = :first and e.lastName = :last");
query.setParameter("first", "Bob");
query.setParameter("last", "Smith");
List<Employee> list = query.getResultList();

// Positional parameters can be specified in JPQL using the syntax ? or ?<position>.
// Positional parameters start at position 1 not 0.

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