对象池(套用了网上的一个有BUG代码自己补充的没实际用过)

此最相思 — Mon, 18 May 2015 10:49:00 GMT

import java.util.Enumeration;
import java.util.Vector;

public class ObjectPool {

    private static final boolean PRINTABLE = true;
    private Class clazz = null;
    private int numObjects = 10;
    private int maxObjects = 50;
    private Vector objects = null;

    public static void main(String[] args) throws Exception {

        ObjectPool pool = new ObjectPool(XX.class);
        pool.createPool();

        XX xx = (XX) pool.getObject();
        xx.reset();
        xx.setAge(1);
        xx.setSex("M");

        pool.returnObject(xx);
        pool.closeObjectPool();
    }


    public ObjectPool(Class clazz) {

        this.clazz = clazz;
    }

    public synchronized void createPool() throws Exception {

        if (this.objects != null)
            return;

        this.objects = new Vector();
        for (int i = 0; i < this.numObjects; ++ i) {

            createObjects();
        }
    }


    public synchronized Object getObject() throws Exception {

        if (this.objects == null)
            return null;

        Object conn = this.getFreeObject();

        while (conn == null) {
            wait(250);
            conn = this.getFreeObject();
        }

        return conn;
    }


    private Object getFreeObject() throws Exception {

        Object obj = this.findFreeObject();

        if (obj == null) {

            this.createObjects();
            obj = this.findFreeObject();
            if (obj == null) {

                return null;
            }
        }

        return obj;
    }

    private void createObjects() throws Exception {

        if (this.objects.size() < this.maxObjects) {

            this.message("created" + this.objects.size());
            Object obj = this.clazz.newInstance();
            this.objects.addElement(new PooledObject(this.objects.size(), obj));
        }
    }


    private Object findFreeObject() {

        this.message("before free:--------");
        this.print();
        Object obj = null;
        PooledObject pooledObject = null;
        Enumeration enumerate = objects.elements();
        while (enumerate.hasMoreElements()) {

            pooledObject = (PooledObject) enumerate.nextElement();
            if (!pooledObject.isBusy()) {

                pooledObject.setBusy(true);
                obj = pooledObject.getObject();
                this.message("free object");
                break;
            }
        }

        this.message("after free:--------");
        this.print();

        return obj;
    }


    public void returnObject(Object obj) {

        if (this.objects == null)
            return;

        this.message("before return:--------");
        this.print();
        PooledObject pooledObject = null;
        Enumeration enumerate = objects.elements();
        while (enumerate.hasMoreElements()) {

            pooledObject = (PooledObject) enumerate.nextElement();
            if (obj == pooledObject.getObject()) {

                pooledObject.setBusy(false);
                this.message("return object");
                break;
            }
        }
        this.message("after return:--------");
        this.print();
    }


    public synchronized void closeObjectPool() {

        if (this.objects == null)
            return;

        PooledObject pooledObject = null;
        Enumeration enumerate = objects.elements();
        while (enumerate.hasMoreElements()) {

            pooledObject = (PooledObject) enumerate.nextElement();
            this.message(pooledObject.toString());
            if (pooledObject.isBusy()) {
                this.message("wait 5000");
                wait(5000);
            }
        }

        this.objects.clear();
        this.objects = null;
    }


    private void wait(int millionSeconds) {

        try {
            Thread.sleep(millionSeconds);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }


    public void print() {

        Enumeration enumerate = objects.elements();
        while (enumerate.hasMoreElements()) {

            PooledObject pooledObject = (PooledObject) enumerate.nextElement();
            this.message(pooledObject.toString());
        }

        this.message("print end==============================");
    }


    public void message(String msg) {

        if (PRINTABLE) {
            System.out.println(msg);
        }
    }


    class PooledObject {

        private int index = 0;
        Object objection = null;// 对象
        boolean busy = false; // 此对象是否正在使用的标志，默认没有正在使用

        // 构造函数，根据一个 Object 构告一个 PooledObject 对象
        public PooledObject(int index, Object objection) {

            this.index = index;
            this.objection = objection;
            this.busy = false;
        }

        // 返回此对象中的对象
        public Object getObject() {
            return objection;
        }

        // 设置此对象的，对象
        public void setObject(Object objection) {
            this.objection = objection;

        }

        // 获得对象对象是否忙
        public boolean isBusy() {
            return busy;
        }

        // 设置对象的对象正在忙
        public void setBusy(boolean busy) {
            this.busy = busy;
        }

        public int getIndex() {
            return index;
        }

        public void setIndex(int index) {
            this.index = index;
        }

        @Override
        public String toString() {

            return String.format("[PooledObject] index:%d, busy:%b", this.index, this.busy);
        }
    }
}

class XX {

    private int age = 0;
    private String sex = "";

    public XX() {

    }

    public void reset() {

        this.age = 0;
        this.sex = "";
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

此最相思 2015-05-18 18:49 发表评论

centos上运行jni

此最相思 — Thu, 07 May 2015 09:14:00 GMT

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.StringTokenizer;

public class Test {

    public static native void hello();
        static final String LIBFILENAME = "/home/my/java/libtest.so";

    static {
        //System.loadLibrary(LIBFILENAME);

        try {
            // 获取到java.library.path  及系统变量中Path中的内容
            String libpath = System.getProperty("java.library.path");
            if (libpath == null || libpath.length() == 0) {
                throw new RuntimeException("java.library.path is null");
            }
            //javaBinPath   jdk的bin目录D:\Program Files\Java\jdk1.6.0_11\bin
            String javaBinPath = null;
            StringTokenizer st = new StringTokenizer(libpath,
                    System.getProperty("path.separator"));
            if (st.hasMoreElements()) {
                javaBinPath = st.nextToken();
            } else {
                throw new RuntimeException("can not split library path:"
                        + libpath);
            }
            // 把dll文件写入到java.library.path中该dll放在ConvertWord2HM相同目录下，这个可以是你的类名
            InputStream inputStream = Test.class.getResourceAsStream(
                    LIBFILENAME);
            final File dllFile = new File(LIBFILENAME);
            if (!dllFile.exists()) {
                FileOutputStream outputStream = new FileOutputStream(dllFile);
                byte[] array = new byte[1024];
                int bytesRead = -1;
                while ((bytesRead = inputStream.read(array)) != -1) {
                    outputStream.write(array, 0, bytesRead);
                }
                outputStream.flush();
                outputStream.close();
            }
            // 动态加载dll
            System.load(dllFile.getPath());
            // 在虚拟机关闭的时候删除dll 这里看着用吧
// dllFile.deleteOnExit();
        } catch (Throwable e) {
            throw new RuntimeException("load Convert.dll error!", e);
        }

    }
    public static void main(String[] args) {
        Test.hello();
    }
}

这个文件是在目录/home/my/java下的
javac Test.java
javah Test //生成Test.h
然后自己写Test.cpp
.java .h .cpp 这些文件名字一定要一样

g++ -I$JAVA_HOME/include -I$JAVA_HOME/include/linux -fPIC -shared -o libtest.so Test.cpp // 转成你想要的文件我这里是libtest.so 也可以是libtest.dll, 看你代码调用什么。
java Test 就可以运行了
用System.loadLibrary() 一直加载不了只能网上找了个加载lib的代码

此最相思 2015-05-07 17:14 发表评论

C++博客-misschuer-随笔分类-Java

对象池(套用了网上的一个有BUG代码 自己补充的 没实际用过)

centos上运行jni

对象池(套用了网上的一个有BUG代码自己补充的没实际用过)