poi/src/testcases/org/apache/poi/hssf/record/common/TestUnicodeString.java

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   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
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package org.apache.poi.hssf.record.common;

import junit.framework.TestCase;

import org.apache.poi.hssf.record.ContinueRecord;
import org.apache.poi.hssf.record.RecordInputStream;
import org.apache.poi.hssf.record.SSTRecord;
import org.apache.poi.hssf.record.cont.ContinuableRecordOutput;

/**
 * Tests that {@link UnicodeString} record size calculates correctly.  The record size
 * is used when serializing {@link SSTRecord}s.
 *
 * @author Jason Height (jheight at apache.org)
 */
public final class TestUnicodeString extends TestCase {
    private static final int MAX_DATA_SIZE = RecordInputStream.MAX_RECORD_DATA_SIZE;

    /** a 4 character string requiring 16 bit encoding */
    private static final String STR_16_BIT = "A\u591A\u8A00\u8A9E";

    private static void confirmSize(int expectedSize, UnicodeString s) {
        confirmSize(expectedSize, s, 0);
    }
    /**
     * Note - a value of zero for <tt>amountUsedInCurrentRecord</tt> would only ever occur just
     * after a {@link ContinueRecord} had been started.  In the initial {@link SSTRecord} this 
     * value starts at 8 (for the first {@link UnicodeString} written).  In general, it can be
     * any value between 0 and {@link #MAX_DATA_SIZE}
     */
    private static void confirmSize(int expectedSize, UnicodeString s, int amountUsedInCurrentRecord) {
        ContinuableRecordOutput out = ContinuableRecordOutput.createForCountingOnly();
        out.writeContinue();
        for(int i=amountUsedInCurrentRecord; i>0; i--) {
            out.writeByte(0);
        }
        int size0 = out.getTotalSize();
        s.serialize(out);
        int size1 = out.getTotalSize();
        int actualSize = size1-size0;
        assertEquals(expectedSize, actualSize);
    }

    public void testSmallStringSize() {
        //Test a basic string
        UnicodeString s = makeUnicodeString("Test");
        confirmSize(7, s);

        //Test a small string that is uncompressed
        s = makeUnicodeString(STR_16_BIT);
        s.setOptionFlags((byte)0x01);
        confirmSize(11, s);

        //Test a compressed small string that has rich text formatting
        s.setString("Test");
        s.setOptionFlags((byte)0x8);
        UnicodeString.FormatRun r = new UnicodeString.FormatRun((short)0,(short)1);
        s.addFormatRun(r);
        UnicodeString.FormatRun r2 = new UnicodeString.FormatRun((short)2,(short)2);
        s.addFormatRun(r2);
        confirmSize(17, s);

        //Test a uncompressed small string that has rich text formatting
        s.setString(STR_16_BIT);
        s.setOptionFlags((byte)0x9);
        confirmSize(21, s);

        //Test a compressed small string that has rich text and extended text
        s.setString("Test");
        s.setOptionFlags((byte)0xC);
        s.setExtendedRst(new byte[]{(byte)0x1,(byte)0x2,(byte)0x3,(byte)0x4,(byte)0x5});
        confirmSize(26, s);

        //Test a uncompressed small string that has rich text and extended text
        s.setString(STR_16_BIT);
        s.setOptionFlags((byte)0xD);
        confirmSize(30, s);
    }

    public void testPerfectStringSize() {
      //Test a basic string
      UnicodeString s = makeUnicodeString(MAX_DATA_SIZE-2-1);
      confirmSize(MAX_DATA_SIZE, s);

      //Test an uncompressed string
      //Note that we can only ever get to a maximim size of 8227 since an uncompressed
      //string is writing double bytes.
      s = makeUnicodeString((MAX_DATA_SIZE-2-1)/2, true);
      s.setOptionFlags((byte)0x1);
      confirmSize(MAX_DATA_SIZE-1, s);
    }

    public void testPerfectRichStringSize() {
      //Test a rich text string
      UnicodeString s = makeUnicodeString(MAX_DATA_SIZE-2-1-8-2);
      s.addFormatRun(new UnicodeString.FormatRun((short)1,(short)0));
      s.addFormatRun(new UnicodeString.FormatRun((short)2,(short)1));
      s.setOptionFlags((byte)0x8);
      confirmSize(MAX_DATA_SIZE, s);

      //Test an uncompressed rich text string
      //Note that we can only ever get to a maximum size of 8227 since an uncompressed
      //string is writing double bytes.
      s = makeUnicodeString((MAX_DATA_SIZE-2-1-8-2)/2, true);
      s.addFormatRun(new UnicodeString.FormatRun((short)1,(short)0));
      s.addFormatRun(new UnicodeString.FormatRun((short)2,(short)1));
      s.setOptionFlags((byte)0x9);
      confirmSize(MAX_DATA_SIZE-1, s);
    }

    public void testContinuedStringSize() {
      //Test a basic string
      UnicodeString s = makeUnicodeString(MAX_DATA_SIZE-2-1+20);
      confirmSize(MAX_DATA_SIZE+4+1+20, s);
    }

    /** Tests that a string size calculation that fits neatly in two records, the second being a continue*/
    public void testPerfectContinuedStringSize() {
      //Test a basic string
      int strSize = MAX_DATA_SIZE*2;
      //String overhead
      strSize -= 3;
      //Continue Record overhead
      strSize -= 4;
      //Continue Record additional byte overhead
      strSize -= 1;
      UnicodeString s = makeUnicodeString(strSize);
      confirmSize(MAX_DATA_SIZE*2, s);
    }


    private static UnicodeString makeUnicodeString(String s) {
      UnicodeString st = new UnicodeString(s);
      st.setOptionFlags((byte)0);
      return st;
    }

    private static UnicodeString makeUnicodeString(int numChars) {
        return makeUnicodeString(numChars, false);
    }
    /**
     * @param is16Bit if <code>true</code> the created string will have characters > 0x00FF
     * @return a string of the specified number of characters
     */
    private static UnicodeString makeUnicodeString(int numChars, boolean is16Bit) {
      StringBuffer b = new StringBuffer(numChars);
      int charBase = is16Bit ? 0x8A00 : 'A';
      for (int i=0;i<numChars;i++) {
        char ch = (char) ((i%16)+charBase);
        b.append(ch);
      }
      return makeUnicodeString(b.toString());
    }
}