foam.lib.csv.Outputter.java Source code

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Here is the source code for foam.lib.csv.Outputter.java

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/**
 * @license
 * Copyright 2017 The FOAM Authors. All Rights Reserved.
 * http://www.apache.org/licenses/LICENSE-2.0
 */

package foam.lib.csv;

import foam.core.*;
import foam.dao.AbstractSink;
import foam.lib.json.OutputterMode;
import foam.util.SafetyUtil;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.TimeZone;
import org.apache.commons.io.IOUtils;

public class Outputter extends AbstractSink implements foam.lib.Outputter {

    protected ThreadLocal<SimpleDateFormat> sdf = new ThreadLocal<SimpleDateFormat>() {
        @Override
        protected SimpleDateFormat initialValue() {
            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
            df.setTimeZone(TimeZone.getTimeZone("UTC"));
            return df;
        }
    };

    protected ClassInfo of_ = null;
    protected List<PropertyInfo> props_ = null;
    protected StringWriter stringWriter_ = null;
    protected PrintWriter writer_;
    protected OutputterMode mode_;
    protected boolean outputHeaders_;
    protected boolean isHeadersOutput_ = false;

    public Outputter() {
        this(OutputterMode.FULL);
    }

    public Outputter(OutputterMode mode) {
        this((PrintWriter) null, mode, true);
    }

    public Outputter(OutputterMode mode, boolean outputHeaders) {
        this((PrintWriter) null, mode, outputHeaders);
    }

    public Outputter(File file, OutputterMode mode, boolean outputHeaders) throws FileNotFoundException {
        this(new PrintWriter(file), mode, outputHeaders);
    }

    public Outputter(OutputStream os, OutputterMode mode, boolean outputHeaders) {
        this(new OutputStreamWriter(os), mode, outputHeaders);
    }

    public Outputter(Writer writer, OutputterMode mode, boolean outputHeaders) {
        this(new PrintWriter(writer), mode, outputHeaders);
    }

    public Outputter(PrintWriter writer, OutputterMode mode, boolean outputHeaders) {
        if (writer == null) {
            stringWriter_ = new StringWriter();
            writer = new PrintWriter(stringWriter_);
        }

        this.mode_ = mode;
        this.writer_ = writer;
        this.outputHeaders_ = outputHeaders;
    }

    public String stringify(FObject obj) {
        if (stringWriter_ == null) {
            stringWriter_ = new StringWriter();
            writer_ = new PrintWriter(stringWriter_);
        }

        stringWriter_.getBuffer().setLength(0);
        if (outputHeaders_)
            outputHeaders(obj);

        outputFObject(obj);
        return this.toString();
    }

    /**
     * Gets a filtered list of properties. Removes network and storage transient variables
     * if necessary, removes unsupported types
     * @param obj the object to get the property list from
     * @return the filtered list of properties
     */
    public List<PropertyInfo> getFilteredPropertyInfoList(FObject obj) {
        if (of_ != null && props_ != null && obj.getClassInfo().equals(of_))
            return props_;

        of_ = obj.getClassInfo();
        props_ = new ArrayList<PropertyInfo>();

        List<PropertyInfo> props = obj.getClassInfo().getAxiomsByClass(PropertyInfo.class);
        for (PropertyInfo prop : props) {
            // filter out network and storage transient values
            if (mode_ == OutputterMode.NETWORK && prop.getNetworkTransient())
                continue;
            if (mode_ == OutputterMode.STORAGE && prop.getStorageTransient())
                continue;

            // filter out unsupported types
            if (prop instanceof AbstractArrayPropertyInfo || prop instanceof AbstractFObjectArrayPropertyInfo
                    || prop instanceof AbstractFObjectPropertyInfo) {
                continue;
            }

            props_.add(prop);
        }

        return props_;
    }

    public void outputHeaders(FObject obj) {
        List<PropertyInfo> props = getFilteredPropertyInfoList(obj);
        Iterator i = props.iterator();

        while (i.hasNext()) {
            PropertyInfo prop = (PropertyInfo) i.next();
            writer_.append(prop.getName());
            if (i.hasNext())
                writer_.append(",");
        }
        writer_.append("\n");
    }

    public String escape(String s) {
        // TODO: make comma escaping configurable
        //
        // options:
        //   escape commas:   , -> \,
        //   remove commas:   , ->
        //   quote strings:   Acme, Inc. -> "Acme, Inc."

        s = s.replace("\n", "\\n").replace("\"", "\\\"");

        // quote strings:   Acme, Inc. -> "Acme, Inc."
        if (s.contains(","))
            return "\"" + s + "\"";
        else
            return s;
    }

    protected void outputString(String s) {
        if (SafetyUtil.isEmpty(s))
            return;
        writer_.append(escape(s));
    }

    protected void outputNumber(Number value) {
        writer_.append(value.toString());
    }

    protected void outputBoolean(Boolean value) {
        writer_.append(value ? "true" : "false");
    }

    protected void outputDate(Date value) {
        outputString(sdf.get().format(value));
    }

    protected void outputFObject(FObject obj) {
        List<PropertyInfo> props = getFilteredPropertyInfoList(obj);
        Iterator i = props.iterator();

        while (i.hasNext()) {
            PropertyInfo prop = (PropertyInfo) i.next();
            prop.toCSV(this, prop.f(obj));
            if (i.hasNext())
                writer_.append(",");
        }
        writer_.append("\n");
    }

    protected void outputList(java.util.List list) {
        writer_.append("[");
        java.util.Iterator iter = list.iterator();
        while (iter.hasNext()) {
            output(iter.next());
            if (iter.hasNext())
                writer_.append(",");
        }
        writer_.append("]");
    }

    public void output(Object value) {
        if (value instanceof String) {
            outputString((String) value);
        } else if (value instanceof Number) {
            outputNumber((Number) value);
        } else if (value instanceof Boolean) {
            outputBoolean((Boolean) value);
        } else if (value instanceof Date) {
            outputDate((Date) value);
        } else if (value instanceof java.util.List) {
            outputList((java.util.List) value);
        }
    }

    @Override
    public String toString() {
        return (stringWriter_ != null) ? stringWriter_.toString() : null;
    }

    @Override
    public void put(Object obj, Detachable sub) {
        if (outputHeaders_ && !isHeadersOutput_) {
            outputHeaders((FObject) obj);
            isHeadersOutput_ = true;
        }
        outputFObject((FObject) obj);
    }

    @Override
    public void close() throws IOException {
        IOUtils.closeQuietly(stringWriter_);
        IOUtils.closeQuietly(writer_);
    }

    @Override
    public void flush() throws IOException {
        if (stringWriter_ != null)
            stringWriter_.flush();
        if (writer_ != null)
            writer_.flush();
    }
}