IOUtils的使用_ioutils.tostring

[转载于http://uule.iteye.com/blog/2107010](http://uule.iteye.com/blog/2107010)

1、IOUtils.toString(InputStream input)

 

protected boolean writeEJBJar(String path, WebServiceProject project){
        String ejbJar = null;
        try {
            ejbJar = IOUtils.toString(this.getClass().getClassLoader().getResourceAsStream("META-INF/ws/ejb-jar.comm.template"));

            logger.debug("get template pass...");

            ejbJar = String.format(ejbJar, project.getName());

            logger.debug("template format :\n" + ejbJar);

            FileUtils.writeStringToFile(new File(path), ejbJar, "UTF-8");

            logger.debug("write " + path + " to harddrive pass...");
        } catch (Exception e) {
            e.printStackTrace();
            logger.error("writeBuild error : " + e.getMessage());
            return false;
        }
        return true;
    }
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源码：

//注意此处用的StringWriter来实现字符输出展示
public static String toString(InputStream input) throws IOException {
        StringWriter sw = new StringWriter();
        copy(input, sw);
        return sw.toString();
    }
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public static void copy(InputStream input, Writer output)
            throws IOException {
        InputStreamReader in = new InputStreamReader(input);
        copy(in, output);
    }


    public static int copy(Reader input, Writer output) throws IOException {
        long count = copyLarge(input, output);
        if (count > Integer.MAX_VALUE) {
            return -1;
        }
        return (int) count;
    }
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/**
     * The default buffer size to use.
     */
    private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;


    public static long copyLarge(Reader input, Writer output) throws IOException {
        char[] buffer = new char[DEFAULT_BUFFER_SIZE];
        long count = 0;
        int n = 0;
        while (-1 != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }
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InputStream  => InputStreamReader => Reader

StringWriter => Writer

 

 

注意此处用的StringWriter来实现字符输出展示

 

获取异常堆栈信息，也是使用StringWriter展示，如：

import java.io.PrintWriter;
import java.io.StringWriter;

public class ExceptionUtils {

    public static String getStackTrace(Throwable t) {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        try {
            t.printStackTrace(pw);
            return sw.toString();
        } finally {
            pw.close();
        }
    }

}
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