Javafx 2 Java fx2我想在保存之前调整图像大小

我制作了一个javafx应用程序（JavaFX2，jdk 7u72），用户可以在其中导入（使用文件选择器）一个图像，并将其存储在一个外部文件夹中

import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ResourceBundle;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
import javafx.stage.FileChooser;


public class FXMLDocumentbilController implements Initializable {


    @FXML
    private void handleButtonAction(ActionEvent event) {
        FileChooser fileChooser = new FileChooser();        
        fileChooser.setInitialDirectory(
        new File(System.getProperty("user.home")));

       fileChooser.getExtensionFilters().addAll(
       new FileChooser.ExtensionFilter("Icons JPG, PNG, GIF", "*.jpg", "*.gif", "*.png") );
       File file = fileChooser.showOpenDialog(null);

       Path sourceFile = Paths.get(file.toString());
       Path destinationFile = Paths.get("c:\\librafolder\\fotomath", file.getName());        

        try {         
            Files.copy(sourceFile, destinationFile);
        } catch (IOException ex) {
            Logger.getLogger(FXMLDocumentbilController.class.getName()).log(Level.SEVERE, null, ex);
        }

    }

    @Override
    public void initialize(URL url, ResourceBundle rb) {
        // TODO
    }    

}

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我希望图像自动减少到25或30 kb或250X250，然后存储在文件夹中。

我从这个网站找到了一个非常好的解决方案

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这段代码是我的javafx应用程序的一部分。用户选择的每个图像文件（可能是2Mb或10MB）都会加载到应用程序中进行显示。这会消耗太多的ram内存。因此，在执行行代码：Files.copy（sourceFile，destinationFile）之前，必须将每个图像文件最小化为25或30 kb；我理解。但是到目前为止，您尝试过什么来实际减小图像/文件大小呢？另外，请记住stackoverflow不是代码工厂。：-）好的，我将尝试解决这个问题，但我没有JavaFX2的经验。然后我发布我找到的任何解决方案，供stackoverflow用户更正。

package bilpir;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URL;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Iterator;
import java.util.ResourceBundle;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
import javafx.stage.FileChooser;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.imageio.stream.FileImageOutputStream;


public class FXMLDocumentbilController implements Initializable {

    @FXML
    private Label label;

    @FXML
    private void handleButtonAction(ActionEvent event) {

        try {         
            //Files.copy(sourceFile, destinationFile);

     float quality = 0.2f;

        Iterator iter = ImageIO.getImageWritersByFormatName("jpeg");  

        ImageWriter writer = (ImageWriter)iter.next();  

        ImageWriteParam iwp = writer.getDefaultWriteParam();  

        iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);  

        iwp.setCompressionQuality(quality);  

        FileChooser fileChooser = new FileChooser();        
        fileChooser.setInitialDirectory(
        new File(System.getProperty("user.home")));

       fileChooser.getExtensionFilters().addAll(
       new FileChooser.ExtensionFilter("Icons JPG, PNG, GIF", "*.jpg", "*.gif", "*.png") );
       File file = fileChooser.showOpenDialog(null);      


       Path sourceFile = Paths.get(file.toString());
       Path destinationFile = Paths.get("c:\\bilpir", file.getName()); 

       FileInputStream inputStream = new FileInputStream(sourceFile.toString());  
       BufferedImage originalImage = ImageIO.read(inputStream); 

        File file2 = new File(destinationFile.toString());  
        FileImageOutputStream output = new FileImageOutputStream(file2);  
        writer.setOutput(output);

        IIOImage image = new IIOImage(originalImage, null, null);  
        writer.write(null, image, iwp);  
        writer.dispose(); 


        } catch (IOException ex) {
            Logger.getLogger(FXMLDocumentbilController.class.getName()).log(Level.SEVERE, null, ex);
        }

    }

    @Override
    public void initialize(URL url, ResourceBundle rb) {
        // TODO
    }    

}