BAEL-1818 A Simple Guide to Connection Pooling in Java (#4823)
* Initial Commit * Update parent pom.xml * Update BasicConnectionPool class * Update BasicConnectionPool class * BAEL-1818 removed code from core-java module, cleaned up a little pom files * BAEL-1818 moved the code from connectionpool.connectionpools package to connectionpool
This commit is contained in:
parent
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commit
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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
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<modelVersion>4.0.0</modelVersion>
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<groupId>com.baeldung.core-java-persistence</groupId>
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<artifactId>core-java-persistence</artifactId>
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<version>0.1.0-SNAPSHOT</version>
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<packaging>jar</packaging>
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<name>core-java-persistence</name>
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<parent>
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<groupId>com.baeldung</groupId>
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<artifactId>parent-java</artifactId>
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<version>0.0.1-SNAPSHOT</version>
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<relativePath>../parent-java</relativePath>
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</parent>
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<dependencies>
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<dependency>
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<groupId>org.assertj</groupId>
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<artifactId>assertj-core</artifactId>
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<version>${assertj-core.version}</version>
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<scope>test</scope>
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</dependency>
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<dependency>
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<groupId>com.h2database</groupId>
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<artifactId>h2</artifactId>
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<version>${h2database.version}</version>
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</dependency>
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<dependency>
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<groupId>org.apache.commons</groupId>
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<artifactId>commons-dbcp2</artifactId>
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<version>${commons-dbcp2.version}</version>
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</dependency>
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<dependency>
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<groupId>com.zaxxer</groupId>
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<artifactId>HikariCP</artifactId>
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<version>${HikariCP.version}</version>
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</dependency>
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<dependency>
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<groupId>com.mchange</groupId>
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<artifactId>c3p0</artifactId>
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<version>${c3p0.version}</version>
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</dependency>
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</dependencies>
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<build>
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<finalName>core-java-persistence</finalName>
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<resources>
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<resource>
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<directory>src/main/resources</directory>
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<filtering>true</filtering>
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</resource>
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</resources>
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</build>
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<properties>
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<assertj-core.version>3.10.0</assertj-core.version>
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<h2database.version>1.4.197</h2database.version>
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<commons-dbcp2.version>2.4.0</commons-dbcp2.version>
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<HikariCP.version>3.2.0</HikariCP.version>
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<c3p0.version>0.9.5.2</c3p0.version>
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</properties>
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</project>
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@ -1,85 +1,92 @@
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package com.baeldung.connectionpool.connectionpools;
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import java.sql.Connection;
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import java.sql.DriverManager;
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import java.sql.SQLException;
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import java.util.ArrayList;
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import java.util.List;
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public class BasicConnectionPool implements ConnectionPool {
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private final String url;
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private final String user;
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private final String password;
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private final List<Connection> connectionPool;
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private final List<Connection> usedConnections = new ArrayList<>();
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private static final int INITIAL_POOL_SIZE = 10;
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private final int MAX_POOL_SIZE = 20;
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public static BasicConnectionPool create(String url, String user, String password) throws SQLException {
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List<Connection> pool = new ArrayList<>(INITIAL_POOL_SIZE);
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for (int i = 0; i < INITIAL_POOL_SIZE; i++) {
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pool.add(createConnection(url, user, password));
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}
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return new BasicConnectionPool(url, user, password, pool);
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}
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private BasicConnectionPool(String url, String user, String password, List<Connection> connectionPool) {
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this.url = url;
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this.user = user;
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this.password = password;
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this.connectionPool = connectionPool;
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}
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@Override
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public Connection getConnection() throws SQLException {
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if (connectionPool.isEmpty()) {
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if (usedConnections.size() < MAX_POOL_SIZE) {
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connectionPool.add(createConnection(url, user, password));
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} else {
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throw new RuntimeException("Maximum pool size reached, no available connections!");
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}
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}
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Connection connection = connectionPool.remove(connectionPool.size() - 1);
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usedConnections.add(connection);
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return connection;
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}
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@Override
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public boolean releaseConnection(Connection connection) {
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connectionPool.add(connection);
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return usedConnections.remove(connection);
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}
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private static Connection createConnection(String url, String user, String password) throws SQLException {
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return DriverManager.getConnection(url, user, password);
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}
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public int getSize() {
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return connectionPool.size() + usedConnections.size();
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}
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@Override
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public String getUrl() {
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return url;
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}
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@Override
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public String getUser() {
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return user;
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}
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@Override
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public String getPassword() {
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return password;
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}
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public void shutdown() throws SQLException {
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usedConnections.forEach(this::releaseConnection);
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for (Connection c : connectionPool) {
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c.close();
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}
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connectionPool.clear();
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}
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}
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package com.baeldung.connectionpool;
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import java.sql.Connection;
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import java.sql.DriverManager;
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import java.sql.SQLException;
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import java.util.ArrayList;
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import java.util.List;
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public class BasicConnectionPool implements ConnectionPool {
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private final String url;
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private final String user;
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private final String password;
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private final List<Connection> connectionPool;
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private final List<Connection> usedConnections = new ArrayList<>();
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private static final int INITIAL_POOL_SIZE = 10;
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private final int MAX_POOL_SIZE = 20;
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public static BasicConnectionPool create(String url, String user, String password) throws SQLException {
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List<Connection> pool = new ArrayList<>(INITIAL_POOL_SIZE);
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for (int i = 0; i < INITIAL_POOL_SIZE; i++) {
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pool.add(createConnection(url, user, password));
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}
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return new BasicConnectionPool(url, user, password, pool);
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}
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private BasicConnectionPool(String url, String user, String password, List<Connection> connectionPool) {
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this.url = url;
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this.user = user;
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this.password = password;
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this.connectionPool = connectionPool;
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}
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@Override
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public Connection getConnection() throws SQLException {
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if (connectionPool.isEmpty()) {
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if (usedConnections.size() < MAX_POOL_SIZE) {
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connectionPool.add(createConnection(url, user, password));
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} else {
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throw new RuntimeException("Maximum pool size reached, no available connections!");
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}
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}
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Connection connection = connectionPool.remove(connectionPool.size() - 1);
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usedConnections.add(connection);
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return connection;
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}
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@Override
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public boolean releaseConnection(Connection connection) {
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connectionPool.add(connection);
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return usedConnections.remove(connection);
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}
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private static Connection createConnection(String url, String user, String password) throws SQLException {
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return DriverManager.getConnection(url, user, password);
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}
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@Override
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public int getSize() {
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return connectionPool.size() + usedConnections.size();
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}
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@Override
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public List<Connection> getConnectionPool() {
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return connectionPool;
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}
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@Override
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public String getUrl() {
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return url;
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}
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@Override
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public String getUser() {
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return user;
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}
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@Override
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public String getPassword() {
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return password;
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}
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@Override
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public void shutdown() throws SQLException {
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usedConnections.forEach(this::releaseConnection);
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for (Connection c : connectionPool) {
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c.close();
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}
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connectionPool.clear();
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}
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}
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package com.baeldung.connectionpool.connectionpools;
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import com.mchange.v2.c3p0.ComboPooledDataSource;
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import java.beans.PropertyVetoException;
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import java.sql.Connection;
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import java.sql.SQLException;
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public class C3poDataSource {
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private static final ComboPooledDataSource cpds = new ComboPooledDataSource();
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static {
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try {
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cpds.setDriverClass("org.h2.Driver");
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cpds.setJdbcUrl("jdbc:h2:mem:test");
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cpds.setUser("user");
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cpds.setPassword("password");
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} catch (PropertyVetoException e) {
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e.printStackTrace();
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}
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}
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public static Connection getConnection() throws SQLException {
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return cpds.getConnection();
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}
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private C3poDataSource(){}
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package com.baeldung.connectionpool;
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import com.mchange.v2.c3p0.ComboPooledDataSource;
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import java.beans.PropertyVetoException;
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import java.sql.Connection;
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import java.sql.SQLException;
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public class C3poDataSource {
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private static final ComboPooledDataSource cpds = new ComboPooledDataSource();
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static {
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try {
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cpds.setDriverClass("org.h2.Driver");
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cpds.setJdbcUrl("jdbc:h2:mem:test");
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cpds.setUser("user");
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cpds.setPassword("password");
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} catch (PropertyVetoException e) {
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e.printStackTrace();
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}
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}
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public static Connection getConnection() throws SQLException {
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return cpds.getConnection();
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}
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private C3poDataSource(){}
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}
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package com.baeldung.connectionpool.connectionpools;
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import java.sql.Connection;
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import java.sql.SQLException;
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import java.util.List;
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public interface ConnectionPool {
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Connection getConnection() throws SQLException;
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boolean releaseConnection(Connection connection);
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String getUrl();
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String getUser();
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String getPassword();
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package com.baeldung.connectionpool;
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import java.sql.Connection;
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import java.sql.SQLException;
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import java.util.List;
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public interface ConnectionPool {
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Connection getConnection() throws SQLException;
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boolean releaseConnection(Connection connection);
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List<Connection> getConnectionPool();
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int getSize();
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String getUrl();
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String getUser();
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String getPassword();
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void shutdown() throws SQLException;;
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}
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package com.baeldung.connectionpool.connectionpools;
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import java.sql.Connection;
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import java.sql.SQLException;
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import org.apache.commons.dbcp2.BasicDataSource;
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public class DBCPDataSource {
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private static final BasicDataSource ds = new BasicDataSource();
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static {
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ds.setUrl("jdbc:h2:mem:test");
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ds.setUsername("user");
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ds.setPassword("password");
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ds.setMinIdle(5);
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ds.setMaxIdle(10);
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ds.setMaxOpenPreparedStatements(100);
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}
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public static Connection getConnection() throws SQLException {
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return ds.getConnection();
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}
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private DBCPDataSource(){}
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}
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package com.baeldung.connectionpool;
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import java.sql.Connection;
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import java.sql.SQLException;
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import org.apache.commons.dbcp2.BasicDataSource;
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public class DBCPDataSource {
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private static final BasicDataSource ds = new BasicDataSource();
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static {
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ds.setUrl("jdbc:h2:mem:test");
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ds.setUsername("user");
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ds.setPassword("password");
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ds.setMinIdle(5);
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ds.setMaxIdle(10);
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ds.setMaxOpenPreparedStatements(100);
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}
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public static Connection getConnection() throws SQLException {
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return ds.getConnection();
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}
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private DBCPDataSource(){}
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}
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package com.baeldung.connectionpool.connectionpools;
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import com.zaxxer.hikari.HikariConfig;
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import com.zaxxer.hikari.HikariDataSource;
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import java.sql.Connection;
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import java.sql.SQLException;
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public class HikariCPDataSource {
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private static final HikariConfig config = new HikariConfig();
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private static final HikariDataSource ds;
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static {
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config.setJdbcUrl("jdbc:h2:mem:test");
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config.setUsername("user");
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config.setPassword("password");
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config.addDataSourceProperty("cachePrepStmts", "true");
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config.addDataSourceProperty("prepStmtCacheSize", "250");
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config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");
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ds = new HikariDataSource(config);
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}
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public static Connection getConnection() throws SQLException {
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return ds.getConnection();
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}
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private HikariCPDataSource(){}
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}
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package com.baeldung.connectionpool;
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import com.zaxxer.hikari.HikariConfig;
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import com.zaxxer.hikari.HikariDataSource;
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import java.sql.Connection;
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import java.sql.SQLException;
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public class HikariCPDataSource {
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private static final HikariConfig config = new HikariConfig();
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private static final HikariDataSource ds;
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static {
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config.setJdbcUrl("jdbc:h2:mem:test");
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config.setUsername("user");
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config.setPassword("password");
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config.addDataSourceProperty("cachePrepStmts", "true");
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config.addDataSourceProperty("prepStmtCacheSize", "250");
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config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");
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ds = new HikariDataSource(config);
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}
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public static Connection getConnection() throws SQLException {
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return ds.getConnection();
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}
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private HikariCPDataSource(){}
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}
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package com.baeldung.connectionpool;
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import com.baeldung.connectionpool.connectionpools.BasicConnectionPool;
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import com.baeldung.connectionpool.connectionpools.ConnectionPool;
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import java.sql.Connection;
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import java.sql.SQLException;
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import java.util.List;
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import static org.assertj.core.api.Assertions.assertThat;
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import static org.junit.Assert.assertTrue;
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import static org.junit.Assert.fail;
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package com.baeldung.connectionpool;
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import com.baeldung.connectionpool.connectionpools.C3poDataSource;
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import java.sql.SQLException;
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import static org.junit.Assert.assertTrue;
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import org.junit.Test;
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@ -1,6 +1,5 @@
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package com.baeldung.connectionpool;
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import com.baeldung.connectionpool.connectionpools.DBCPDataSource;
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import java.sql.SQLException;
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import static org.junit.Assert.assertTrue;
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import org.junit.Test;
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@ -1,6 +1,5 @@
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package com.baeldung.connectionpool;
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import com.baeldung.connectionpool.connectionpools.HikariCPDataSource;
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import java.sql.SQLException;
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import static org.junit.Assert.assertTrue;
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import org.junit.Test;
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@ -158,21 +158,6 @@
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<artifactId>jmimemagic</artifactId>
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<version>${jmime-magic.version}</version>
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</dependency>
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<dependency>
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<groupId>org.apache.commons</groupId>
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<artifactId>commons-dbcp2</artifactId>
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<version>${commons-dbcp2.version}</version>
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</dependency>
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<dependency>
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<groupId>com.zaxxer</groupId>
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<artifactId>HikariCP</artifactId>
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<version>${HikariCP.version}</version>
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</dependency>
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<dependency>
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||||
<groupId>com.mchange</groupId>
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<artifactId>c3p0</artifactId>
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||||
<version>${c3p0.version}</version>
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</dependency>
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<!-- instrumentation -->
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<dependency>
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<groupId>org.javassist</groupId>
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@ -544,11 +529,6 @@
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<!-- testing -->
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<assertj-core.version>3.10.0</assertj-core.version>
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<!-- JDBC pooling frameworks -->
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<commons-dbcp2.version>2.4.0</commons-dbcp2.version>
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<HikariCP.version>3.2.0</HikariCP.version>
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<c3p0.version>0.9.5.2</c3p0.version>
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<!-- maven plugins -->
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<maven-surefire-plugin.version>2.19.1</maven-surefire-plugin.version>
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<springframework.spring-web.version>4.3.4.RELEASE</springframework.spring-web.version>
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||||
|
|
25
pom.xml
25
pom.xml
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@ -312,6 +312,7 @@
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|||
<module>core-java-collections</module>
|
||||
<module>core-java-io</module>
|
||||
<module>core-java-8</module>
|
||||
<module>core-java-persistence</module>
|
||||
<module>core-kotlin</module>
|
||||
<module>core-groovy</module>
|
||||
<module>core-java-concurrency</module>
|
||||
|
@ -877,7 +878,7 @@
|
|||
<module>spring-static-resources</module>
|
||||
<module>hazelcast</module>
|
||||
<module>hbase</module>
|
||||
|
||||
|
||||
<module>hystrix</module>
|
||||
<module>image-processing</module>
|
||||
<module>immutables</module>
|
||||
|
@ -906,11 +907,11 @@
|
|||
<module>linkrest</module>
|
||||
<module>logging-modules/log-mdc</module>
|
||||
<module>logging-modules/log4j</module>
|
||||
|
||||
|
||||
<module>logging-modules/logback</module>
|
||||
<module>lombok</module>
|
||||
<module>mapstruct</module>
|
||||
|
||||
|
||||
<module>maven</module>
|
||||
<module>mesos-marathon</module>
|
||||
<module>msf4j</module>
|
||||
|
@ -962,25 +963,25 @@
|
|||
<module>spring-cucumber</module>
|
||||
<module>spring-ejb</module>
|
||||
<module>spring-aop</module>
|
||||
|
||||
|
||||
<module>persistence-modules/spring-data-dynamodb</module>
|
||||
<module>spring-data-keyvalue</module>
|
||||
<module>spring-data-mongodb</module>
|
||||
<module>persistence-modules/spring-data-neo4j</module>
|
||||
|
||||
|
||||
<module>spring-data-rest</module>
|
||||
<module>persistence-modules/spring-data-solr</module>
|
||||
<module>spring-dispatcher-servlet</module>
|
||||
<module>spring-exceptions</module>
|
||||
<module>spring-freemarker</module>
|
||||
<module>persistence-modules/spring-hibernate-3</module>
|
||||
|
||||
|
||||
<module>persistence-modules/spring-hibernate-5</module>
|
||||
<module>persistence-modules/spring-data-eclipselink</module>
|
||||
<module>spring-integration</module>
|
||||
<module>spring-jenkins-pipeline</module>
|
||||
<module>spring-jersey</module>
|
||||
|
||||
|
||||
<module>spring-jms</module>
|
||||
<module>spring-jooq</module>
|
||||
<module>persistence-modules/spring-jpa</module>
|
||||
|
@ -1041,13 +1042,13 @@
|
|||
<module>testing-modules/testing</module>
|
||||
<module>testing-modules/testng</module>
|
||||
<module>video-tutorials</module>
|
||||
|
||||
|
||||
<module>xmlunit-2</module>
|
||||
<module>struts-2</module>
|
||||
<module>apache-velocity</module>
|
||||
<module>apache-solrj</module>
|
||||
<module>rabbitmq</module>
|
||||
|
||||
|
||||
<module>persistence-modules/spring-data-gemfire</module>
|
||||
<module>mybatis</module>
|
||||
<module>spring-drools</module>
|
||||
|
@ -1090,7 +1091,7 @@
|
|||
<module>vertx</module>
|
||||
<module>metrics</module>
|
||||
<module>httpclient</module>
|
||||
|
||||
|
||||
<module>jmeter</module>
|
||||
-->
|
||||
|
||||
|
@ -1233,6 +1234,4 @@
|
|||
<!-- <maven-pmd-plugin.version>3.9.0</maven-pmd-plugin.version> -->
|
||||
<maven-pmd-plugin.version>3.8</maven-pmd-plugin.version>
|
||||
</properties>
|
||||
|
||||
</project>
|
||||
|
||||
</project>
|
Loading…
Reference in New Issue