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JDBC removed...

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This commit is contained in:
Amit Dixit 2016-04-04 12:33:43 +05:30
parent deb15e2733
commit eb72493f13
4 changed files with 140 additions and 19 deletions
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14
data-mapper/src/main/java/com/iluwatar/datamapper/App.java
View File

@ -83,11 +83,15 @@ public final class App {
/* Add student in respectibe db */
mapper.insert(student);
if (log.isDebugEnabled()) {
log.debug("App.main(), student : " + student + ", is inserted");
}
/* Find this student */
final Optional<Student> studentToBeFound = mapper.find(student.getStudentId());
if (log.isDebugEnabled()) {
log.debug("App.main(), db find returned : " + studentToBeFound);
log.debug("App.main(), student : " + studentToBeFound + ", is searched");
}
/* Update existing student object */
@ -96,7 +100,15 @@ public final class App {
/* Update student in respectibe db */
mapper.update(student);
if (log.isDebugEnabled()) {
log.debug("App.main(), student : " + student + ", is updated");
}
/* Delete student in db */
if (log.isDebugEnabled()) {
log.debug("App.main(), student : " + student + ", is deleted");
}
mapper.delete(student);
}

23
data-mapper/src/main/java/com/iluwatar/datamapper/StudentMySQLDataMapper.java
View File

@ -18,19 +18,20 @@
*/
package com.iluwatar.datamapper;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
public final class StudentMySQLDataMapper implements StudentDataMapper {
/* Note: Normally this would be in the form of an actual database */
private List<Student> students;
private List<Student> students = new ArrayList<>();
@Override
public final Optional<Student> find(final int studentId) {
/* Compare with existing students */
for (final Student student : this.students) {
for (final Student student : this.getStudents()) {
/* Check if student is found */
if (student.getStudentId() == studentId) {
@ -48,13 +49,13 @@ public final class StudentMySQLDataMapper implements StudentDataMapper {
/* Check with existing students */
if (this.students.contains(studentToBeUpdated)) {
if (this.getStudents().contains(studentToBeUpdated)) {
/* Get the index of student in list */
final int index = this.students.indexOf(studentToBeUpdated);
final int index = this.getStudents().indexOf(studentToBeUpdated);
/* Update the student in list */
this.students.set(index, studentToBeUpdated);
this.getStudents().set(index, studentToBeUpdated);
} else {
@ -67,10 +68,10 @@ public final class StudentMySQLDataMapper implements StudentDataMapper {
public final void insert(final Student studentToBeInserted) throws DataMapperException {
/* Check with existing students */
if (!this.students.contains(studentToBeInserted)) {
if (!this.getStudents().contains(studentToBeInserted)) {
/* Add student in list */
this.students.add(studentToBeInserted);
this.getStudents().add(studentToBeInserted);
} else {
@ -83,10 +84,10 @@ public final class StudentMySQLDataMapper implements StudentDataMapper {
public final void delete(final Student studentToBeDeleted) throws DataMapperException {
/* Check with existing students */
if (this.students.contains(studentToBeDeleted)) {
if (this.getStudents().contains(studentToBeDeleted)) {
/* Delete the student from list */
this.students.remove(studentToBeDeleted);
this.getStudents().remove(studentToBeDeleted);
} else {
@ -94,4 +95,8 @@ public final class StudentMySQLDataMapper implements StudentDataMapper {
throw new DataMapperException("Student [" + studentToBeDeleted.getName() + "] is not found");
}
}
public List<Student> getStudents() {
return this.students;
}
}

23
data-mapper/src/main/java/com/iluwatar/datamapper/StudentOracleDataMapper.java
View File

@ -18,19 +18,20 @@
*/
package com.iluwatar.datamapper;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
public final class StudentOracleDataMapper implements StudentDataMapper {
/* Note: Normally this would be in the form of an actual database */
private List<Student> students;
private List<Student> students = new ArrayList<>();
@Override
public final Optional<Student> find(final int studentId) {
/* Compare with existing students */
for (final Student student : this.students) {
for (final Student student : this.getStudents()) {
/* Check if student is found */
if (student.getStudentId() == studentId) {
@ -48,13 +49,13 @@ public final class StudentOracleDataMapper implements StudentDataMapper {
/* Check with existing students */
if (this.students.contains(studentToBeUpdated)) {
if (this.getStudents().contains(studentToBeUpdated)) {
/* Get the index of student in list */
final int index = this.students.indexOf(studentToBeUpdated);
final int index = this.getStudents().indexOf(studentToBeUpdated);
/* Update the student in list */
this.students.set(index, studentToBeUpdated);
this.getStudents().set(index, studentToBeUpdated);
} else {
@ -67,10 +68,10 @@ public final class StudentOracleDataMapper implements StudentDataMapper {
public final void insert(final Student studentToBeInserted) throws DataMapperException {
/* Check with existing students */
if (!this.students.contains(studentToBeInserted)) {
if (!this.getStudents().contains(studentToBeInserted)) {
/* Add student in list */
this.students.add(studentToBeInserted);
this.getStudents().add(studentToBeInserted);
} else {
@ -83,10 +84,10 @@ public final class StudentOracleDataMapper implements StudentDataMapper {
public final void delete(final Student studentToBeDeleted) throws DataMapperException {
/* Check with existing students */
if (this.students.contains(studentToBeDeleted)) {
if (this.getStudents().contains(studentToBeDeleted)) {
/* Delete the student from list */
this.students.remove(studentToBeDeleted);
this.getStudents().remove(studentToBeDeleted);
} else {
@ -94,4 +95,8 @@ public final class StudentOracleDataMapper implements StudentDataMapper {
throw new DataMapperException("Student [" + studentToBeDeleted.getName() + "] is not found");
}
}
public List<Student> getStudents() {
return this.students;
}
}

99
data-mapper/src/test/java/com/iluwatar/datamapper/AppTest.java Normal file
View File

@ -0,0 +1,99 @@
/**
* The MIT License Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
* associated documentation files (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge, publish, distribute,
* sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or
* substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
* NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package com.iluwatar.datamapper;
import java.util.Optional;
import java.util.UUID;
import org.apache.log4j.Logger;
/**
* The Data Mapper (DM) is a layer of software that separates the in-memory objects from the
* database. Its responsibility is to transfer data between the two and also to isolate them from
* each other. With Data Mapper the in-memory objects needn't know even that there's a database
* present; they need no SQL interface code, and certainly no knowledge of the database schema. (The
* database schema is always ignorant of the objects that use it.) Since it's a form of Mapper ,
* Data Mapper itself is even unknown to the domain layer.
* <p>
* The below example demonstrates basic CRUD operations: select, add, update, and delete.
*
*/
public final class App {
private static Logger log = Logger.getLogger(App.class);
private static final String DB_TYPE_ORACLE = "Oracle";
private static final String DB_TYPE_MYSQL = "MySQL";
/**
* Program entry point.
*
* @param args command line args.
*/
public static final void main(final String... args) {
if (log.isInfoEnabled() & args.length > 0) {
log.debug("App.main(), db type: " + args[0]);
}
StudentDataMapper mapper = null;
/* Check the desired db type from runtime arguments */
if (DB_TYPE_ORACLE.equalsIgnoreCase(args[0])) {
/* Create new data mapper for mysql */
mapper = new StudentMySQLDataMapper();
} else if (DB_TYPE_MYSQL.equalsIgnoreCase(args[0])) {
/* Create new data mapper for oracle */
mapper = new StudentMySQLDataMapper();
} else {
/* Don't couple any Data Mapper to java.sql.SQLException */
throw new DataMapperException("Following data source(" + args[0] + ") is not supported");
}
/* Create new student */
Student student = new Student(UUID.randomUUID(), 1, "Adam", 'A');
/* Add student in respectibe db */
mapper.insert(student);
/* Find this student */
final Optional<Student> studentToBeFound = mapper.find(student.getGuId());
if (log.isDebugEnabled()) {
log.debug("App.main(), db find returned : " + studentToBeFound);
}
/* Update existing student object */
student = new Student(student.getGuId(), 1, "AdamUpdated", 'A');
/* Update student in respectibe db */
mapper.update(student);
/* Delete student in db */
mapper.delete(student);
}
private App() {}
}