setcharacterencodingfilter.java

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package filter;
import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class SetCharacterEncodingFilter implements Filter {
  protected String encoding = null;
  protected FilterConfig filterConfig = null;
  protected boolean ignore = true;

  public void init(FilterConfig filterConfig) throws ServletException {
    this.filterConfig=filterConfig;
    this.encoding=filterConfig.getInitParameter("encoding");
    String value=filterConfig.getInitParameter("ignore");
    if(value==null)
      this.ignore=true;
    else if(value.equalsIgnoreCase("true"))
      this.ignore=true;
    else
      this.ignore=false;
  }

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
  // TODO 自动生成方法存根
  if (ignore || (request.getCharacterEncoding() == null)) {
    String encoding = selectEncoding(request);
    if (encoding != null)
      request.setCharacterEncoding(encoding);
  }
  chain.doFilter(request, response);
}

public void destroy() {
  // TODO 自动生成方法存根
  this.encoding = null;
  this.filterConfig = null;
}

protected String selectEncoding(ServletRequest request) {
  return (this.encoding);
}
}