Java URL Load readURL(String url, String charsetName)

Description

read URL

License

Open Source License

Declaration

public static String readURL(String url, String charsetName) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Main {

    public static String readURL(String url, String charsetName) {
        try {/*from   w  w  w.  ja va2s.  co  m*/
            java.net.URL u = new java.net.URL(url);
            return readAsText(u.openStream(), charsetName);
        } catch (Exception exp) {
            throw new RuntimeException("readURL error!", exp);
        }
    }

    public static String readAsText(String fileName, String charsetName) {
        InputStream is = null;
        try {
            is = openFile(fileName);
            return readAsText(is, charsetName);
        } catch (Exception exp) {
            throw new RuntimeException("readTextFile error, file: " + fileName, exp);
        } finally {
            close(is);
        }
    }

    public static String readAsText(InputStream is, String charsetName) {
        try {
            StringBuffer sb = new StringBuffer();
            char[] buffer = new char[10000];
            InputStreamReader isr = null;
            if (charsetName != null) {
                isr = new InputStreamReader(is, charsetName);
            } else {
                isr = new InputStreamReader(is);
            }
            int length;
            while ((length = isr.read(buffer)) != -1) {
                sb.append(buffer, 0, length);
            }
            return sb.toString();
        } catch (Exception exp) {
            throw new RuntimeException("readTextInputStream error!", exp);
        }
    }

    public static InputStream openFile(File file) {
        try {
            InputStream is = new FileInputStream(file);
            return is;
        } catch (Exception exp) {
            throw new RuntimeException("openFile error, file: " + file, exp);
        }
    }

    public static InputStream openFile(String name) {
        try {
            return openFile(new File(name));
        } catch (Exception exp) {
            throw new RuntimeException("openFile error, file: " + name, exp);
        }
    }

    public static void close(Closeable resource) {
        try {
            if (resource != null) {
                resource.close();
            }
        } catch (IOException exp) {
            exp.printStackTrace();
        }
    }

    public static byte[] read(File file) {
        return read(openFile(file));
    }

    public static byte[] read(InputStream is) {
        List<byte[]> bufferList = new ArrayList<byte[]>();
        List<Integer> lengthList = new ArrayList<Integer>();
        int total = 0;
        try {
            do {
                byte[] buffer = new byte[10000];
                int length;
                length = is.read(buffer);
                if (length == -1) {
                    break;
                }
                total += length;
                bufferList.add(buffer);
                lengthList.add(length);
            } while (true);
            byte[] result = new byte[total];
            int offset = 0;
            for (int i = 0; i < bufferList.size(); i++) {
                byte[] buf = (byte[]) bufferList.get(i);
                int len = (Integer) lengthList.get(i);
                System.arraycopy(buf, 0, result, offset, len);
                offset += len;
            }
            return result;
        } catch (Exception exp) {
            throw new RuntimeException("readInputStream error!", exp);
        }
    }

    public static byte[] read(File file, int offset, int length) {
        BufferedInputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(file));
            byte[] result = new byte[length];
            is.skip(offset);
            int len = is.read(result);
            if (len < length) {
                result = Arrays.copyOfRange(result, 0, len);
            }
            return result;
        } catch (Exception exp) {
            throw new RuntimeException("writeFile error, file: " + file, exp);
        } finally {
            close(is);
        }
    }
}

Related

1. readUrl(final URL url)
2. readURL(final URL url)
3. readURL(String url)
4. readURL(String url)
5. readURL(String URL)
6. ReadURL(String URLAddress)
7. readUrl(String urlString)
8. readURL(URL fileURL)
9. readURL(URL url)