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Spring lookup-method example to inject prototype scoped bean into a singleton scoped bean

Step 1: You need asm and cgilib libraries in addition to Spring libraries shown below.

Step 2: define the Dao (Data Access Object) interface.

package com.mycompany.understanding.spring;

public interface MyDao {
  abstract void printData();
}

package com.mycompany.understanding.spring;

public interface MyDao {

abstract void printData();

}

Step 3: Define the Dao implementation.

…

Spring MVC RESTful with JPA, Hibernate & MySQL database beginner in 13 steps

This tutorial combines both

1) Spring 4 MVC RESTful Web Service Beginner Tutorial step by step, which focuses on the RSTful web service and

2) JPA with Hibernate & MySQL database tutorial step by step, which focuses on JPA and Hibernate.

…

Spring MVC Web Application with JPA, Hibernate & MySQL

Controller –Service Layer –DAO Layer –JPA/Hibernate –MySQL Database

Step 1: The pom.xml with JSTL, Spring MVC, JPA, and Hibernate libraries are included as well.

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.mytutorial</groupId>
    <artifactId>simple-orm-persistence</artifactId>
    <packaging>war</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>simple-orm-persistence</name>
    <url>http://maven.apache.org</url>

    <properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>

        <!-- MySQL Driver -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>6.0.6</version>
        </dependency>

        <!-- For connection pooling -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-c3p0</artifactId>
            <version>5.2.10.Final</version>
        </dependency>

        <dependency>
            <groupId>javax.persistence</groupId>
            <artifactId>persistence-api</artifactId>
            <version>1.0.2</version>
        </dependency>

        <!-- Hibernate -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>5.2.10.Final</version>
            <exclusions>
                <exclusion>
                    <groupId>org.hibernate.javax.persistence</groupId>
                    <artifactId>hibernate-jpa-2.1-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <!-- Servlet -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>compile</scope>
        </dependency>

        <!-- Spring MVC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.9.RELEASE</version>
        </dependency>

        <!-- JSON data binding -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.8.9</version>
        </dependency>
        <!-- XML data binding -->
        <dependency>
            <groupId>com.fasterxml.jackson.dataformat</groupId>
            <artifactId>jackson-dataformat-xml</artifactId>
            <version>2.8.9</version>
        </dependency>
        
        <!-- JSTL -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

    </dependencies>
    
    <build>
        <finalName>simpleWeb</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.1.0</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

<groupId>com.mytutorial</groupId>

<artifactId>simple-orm-persistence</artifactId>

<version>1.0-SNAPSHOT</version>

<name>simple-orm-persistence</name>

<url>http://maven.apache.org</url>

<maven.compiler.source>1.8</maven.compiler.source>

<maven.compiler.target>1.8</maven.compiler.target>

<java.version>1.8</java.version>

</properties>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

</dependency>

<groupId>mysql</groupId>

<artifactId>mysql-connector-java</artifactId>

</dependency>

<groupId>org.hibernate</groupId>

<artifactId>hibernate-c3p0</artifactId>

<version>5.2.10.Final</version>

</dependency>

<groupId>javax.persistence</groupId>

<artifactId>persistence-api</artifactId>

</dependency>

<groupId>org.hibernate</groupId>

<artifactId>hibernate-entitymanager</artifactId>

<version>5.2.10.Final</version>

<groupId>org.hibernate.javax.persistence</groupId>

<artifactId>hibernate-jpa-2.1-api</artifactId>

</exclusion>

</exclusions>

</dependency>

<groupId>javax.servlet</groupId>

<artifactId>javax.servlet-api</artifactId>

<scope>compile</scope>

</dependency>

<groupId>org.springframework</groupId>

<artifactId>spring-webmvc</artifactId>

<version>4.3.9.RELEASE</version>

</dependency>

<groupId>com.fasterxml.jackson.core</groupId>

<artifactId>jackson-databind</artifactId>

</dependency>

<groupId>com.fasterxml.jackson.dataformat</groupId>

<artifactId>jackson-dataformat-xml</artifactId>

</dependency>

<groupId>javax.servlet</groupId>

</dependency>

</dependencies>

<build>

<finalName>simpleWeb</finalName>

<groupId>org.apache.maven.plugins</groupId>

<artifactId>maven-war-plugin</artifactId>

<failOnMissingWebXml>false</failOnMissingWebXml>

</configuration>

</plugin>

</plugins>

</build>

</project>

Define the model class Account.java

Step 2: Define the Account.java with 3 fields &

…

Spring tutorial to read .proprties files

Q1. How do you read properties file in spring?
A1. PropertyPlaceholderConfigurer allows you to share a properties files. You can simply share one properties file for all of your build info or you can separate things out, and have multiple properties files in your build script.

…

SQL Tutorial with HSQLDB

This assumes that you have Java setup Java on your machine as illustrated in the “setting up” Java tutorial.

Q. Why use HSQLB?
A. It can be useful in a number of ways.

Easy to get started and if you are a beginner,

…

SSH Login without password so that tasks can be automated via shell scripts

Prerequisite

If “openssh-server” & “openssh-client” are not installed in say “hostA”, then install them in “hostA” using “apt-get” with “sudo” for actions with root user privileges.


userA@hostA:~> sudo apt-get install openssh-server openssh-client

userA@hostA:~> sudo apt-get install openssh-server openssh-client

Setting up passwordless connection

The aim is to connect from “hostA”

…

Top 10 Eclipse short-cut keys every Java developer using eclipse IDE must know

1. CTRL+1

Probably the most useful one. It activates the quick fix and generates lots of code for you. This means less typing.

Generating local variables: For example, if you have written a method call and you highlight it and press Ctrl+1,

…

Top 6 Java 8 features you can start using now

Unlike Java 7, Java 8 has some significant changes. You can get familiarised with the the following simple working code. All you need is Java 8 installed on your machine.

#1: Interface can have static and default methods. This tries to solve the diamond (aka multiple inheriance) issue.

…

Top 6 Spring wiring via JavaConfig [i.e. @Configuration ] examples

Spring Java Configuration (i.e. JavaConfig) provides a pure-Java means of configuring the Spring IoC container. This is gaining popularity as it

gives complete control over instantiation and dependency injection.
gives type safety & compile-time check
supports refactorable configuration & supported by IDEs

Here are some industrial strength wiring examples.

…

Understanding Cloudera Hadoop users

Step 1: A number of special users are created by default when installing and using CDH and Cloudera Manager. For example

Unix user id: hdfs
groups: hdfs hadoop

Unix user id: spark
groups: spark

Unix user id: hive
groups: hive

and so on.

…

Understanding Java 8 Streams and working with collections using Lambda expressions

A stream is an infinite sequence of consumable elements (i.e a data structure) for the consumption of an operation or iteration. Any Collection can be exposed as a stream. The operations you perform on a stream can either be intermediate (map, filter, sorted, … Read more ›...

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Unix remoting interview Q&A for Java developers

Q1 How will you delete files that are older than 7 days in a remote unix server?
A1 By ssh ing to the remote host server

ssh user@host123 "find /etc/data/*.csv -mtime +7 -exec rm -f {} \;" >> myapp.log 2>&1

1	ssh user@host123 "find /etc/data/*.csv -mtime +7 -exec rm -f {} \;" >> myapp.log 2>&1

Q2 How will you copy files from a remote server to a local server?

…

Unix script to archive files for auditing

Q1. How will you move files that are older than X (e.g 7) days to their own archive folders to be zipped later on? A1.

#!/bin/sh -x

# DIRPATH=$1    --  path to source files
# ARCPATH=$2    --  path to move archived files 
# WAITTIME=$3   --  days to archive e.g +7 files (older than 7 days)

DIRPATH=$1  
ARCPATH=$2  
WAITTIME=$3 

if [ ! -d $ARCPATH ]; then
    mkdir $ARCPATH
fi

cd $DIRPATH


FILES=`/usr/bin/find . ! -name . -prune -type f -mtime $WAITTIME`

for file in $FILES
do
 #for each file find the creating date so that it can be archived under that directory
 #returns something like 2013Apr26
 DATE=` ls -e  $file| awk '{print $11"-"$8"-"$9}' | sed 's/-//g'` 

 if [ ! -d $ARCPATH/$DATE ]; then
    mkdir $ARCPATH/$DATE
 fi

 echo "Moving " $file " to " $ARCPATH/$DATE
 mv $file $ARCPATH/$DATE 
done;

exit 0

#!/bin/sh -x

# DIRPATH=$1 -- path to source files

# ARCPATH=$2 -- path to move archived files

# WAITTIME=$3 -- days to archive e.g +7 files (older than 7 days)

DIRPATH=$1

ARCPATH=$2

WAITTIME=$3

if [ ! -d $ARCPATH ]; then

mkdir $ARCPATH

cd $DIRPATH

FILES=`/usr/bin/find . ! -name . -prune -type f -mtime $WAITTIME`

for file in $FILES

#for each file find the creating date so that it can be archived under that directory

#returns something like 2013Apr26

DATE=` ls -e $file| awk '{print $11"-"$8"-"$9}' | sed 's/-//g'`

if [ ! -d $ARCPATH/$DATE ]; then

mkdir $ARCPATH/$DATE

echo "Moving " $file " to " $ARCPATH/$DATE

mv $file $ARCPATH/$DATE

done;

exit 0

you run it like

sh archive.sh /etc/myapp /etc/archive +7

1	sh archive.sh /etc/myapp /etc/archive +7

The files will be archived under “/etc/archive/{date}” … Read more ›...

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« 1 … 25 26 27 28 29 30 »

Blog Archives

Spring lookup-method example to inject prototype scoped bean into a singleton scoped bean

Spring MVC RESTful with JPA, Hibernate & MySQL database beginner in 13 steps

Spring MVC Web Application with JPA, Hibernate & MySQL

Spring tutorial to read .proprties files

SQL Tutorial with HSQLDB

SSH Login without password so that tasks can be automated via shell scripts

Top 10 Eclipse short-cut keys every Java developer using eclipse IDE must know

Top 6 Java 8 features you can start using now

Top 6 Spring wiring via JavaConfig [i.e. @Configuration ] examples

Understanding Cloudera Hadoop users

Understanding Java 8 Streams and working with collections using Lambda expressions

Unix remoting interview Q&A for Java developers

Unix script to archive files for auditing

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