com.quartzdesk.executor.common.spring.SpringContext.java Source code

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Here is the source code for com.quartzdesk.executor.common.spring.SpringContext.java

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/*
 * Copyright (c) 2015-2016 QuartzDesk.com.
 * Licensed under the MIT license (https://opensource.org/licenses/MIT).
 */

package com.quartzdesk.executor.common.spring;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

/**
 * Simple wrapper around the Spring application context that
 * provides easy access to the Spring application context from
 * all parts of the application. It also provides generified
 * {@code getBean} methods to avoid casts in the application code.
 */
public class SpringContext {
    private static final Logger log = LoggerFactory.getLogger(SpringContext.class);

    private ApplicationContext appCtx;

    /**
     * Creates a new {@link SpringContext} instance wrapping the specified
     * application context.
     *
     * @param appCtx an application context instance to wrap.
     */
    protected SpringContext(ApplicationContext appCtx) {
        this.appCtx = appCtx;
    }

    /**
     * Returns the {@link SpringContext} instance wrapping the specified
     * application context.
     *
     * @param appCtx an application context.
     * @return the {@link SpringContext} instance wrapping the specified
     *         application context.
     */
    public static SpringContext forContext(ApplicationContext appCtx) {
        return new SpringContext(appCtx);
    }

    /**
     * Returns the {@link SpringContext} instance wrapping a new application
     * context whose configuration is read from the specified classpath resource.
     *
     * @param resource an application context configuration classpath resource.
     * @return the {@link SpringContext} instance wrapping the created
     *         application context.
     */
    public static SpringContext forClasspathResource(String resource) {
        return new SpringContext(new ClassPathXmlApplicationContext(resource));
    }

    /**
     * Returns the {@link SpringContext} instance wrapping a new application
     * context whose configuration is read from the specified file path.
     *
     * @param filePath an application context configuration file path.
     * @return the {@link SpringContext} instance wrapping the created
     *         application context.
     */
    public static SpringContext forFileSystemResource(String filePath) {
        return new SpringContext(new FileSystemXmlApplicationContext(filePath));
    }

    /**
     * Returns the {@link SpringContext} instance wrapping the current
     * application context. This method is typically used to access
     * the application context from application components that are not
     * registered Spring beans.
     *
     * @return the {@link SpringContext} instance wrapping the current
     *         application context.
     */
    public static SpringContext getCurrent() {
        return new SpringContext(ApplicationContextProvider.getApplicationContext());
    }

    /**
     * Returns the bean with the specified name.
     *
     * @param name a bean name.
     * @return the bean instance.
     */
    @SuppressWarnings("unchecked")
    public <T> T getBean(String name) {
        return (T) appCtx.getBean(name);
    }

    /**
     * Returns the bean with the specified name and type (can be an interface, or superclass).
     *
     * @param name a bean name.
     * @param beanType a required bean type.
     * @return the bean instance.
     */
    @SuppressWarnings("unchecked")
    public <T> T getBean(String name, Class<T> beanType) {
        return appCtx.getBean(name, beanType);
    }

    /**
     * Returns the bean with the specified type (can be an interface, or superclass).
     *
     * @param beanType a bean type.
     * @return the bean instance.
     */
    @SuppressWarnings("unchecked")
    public <T> T getBean(Class<T> beanType) {
        return (T) appCtx.getBean(beanType);
    }
}