Android example source code file (XmlBlock.java)

This example Android source code file (XmlBlock.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, end_document, end_tag, io, name, object, runtimeexception, start_document, start_tag, string, stringblock, text, throwable, util, utilities, utils, xmlblock, xmlpullparserexception, xmlpullparserexception,ioexception

The XmlBlock.java Android example source code

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.content.res;

import android.util.TypedValue;

import com.android.internal.util.XmlUtils;

import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;

/**
 * Wrapper around a compiled XML file.
 * 
 * {@hide}
 */
final class XmlBlock {
    private static final boolean DEBUG=false;

    public XmlBlock(byte[] data) {
        mAssets = null;
        mNative = nativeCreate(data, 0, data.length);
        mStrings = new StringBlock(nativeGetStringBlock(mNative), false);
    }

    public XmlBlock(byte[] data, int offset, int size) {
        mAssets = null;
        mNative = nativeCreate(data, offset, size);
        mStrings = new StringBlock(nativeGetStringBlock(mNative), false);
    }

    public void close() {
        synchronized (this) {
            if (mOpen) {
                mOpen = false;
                decOpenCountLocked();
            }
        }
    }

    private void decOpenCountLocked() {
        mOpenCount--;
        if (mOpenCount == 0) {
            nativeDestroy(mNative);
            if (mAssets != null) {
                mAssets.xmlBlockGone(hashCode());
            }
        }
    }

    public XmlResourceParser newParser() {
        synchronized (this) {
            if (mNative != 0) {
                return new Parser(nativeCreateParseState(mNative), this);
            }
            return null;
        }
    }

    /*package*/ final class Parser implements XmlResourceParser {
        Parser(int parseState, XmlBlock block) {
            mParseState = parseState;
            mBlock = block;
            block.mOpenCount++;
        }

        public void setFeature(String name, boolean state) throws XmlPullParserException {
            if (FEATURE_PROCESS_NAMESPACES.equals(name) && state) {
                return;
            }
            if (FEATURE_REPORT_NAMESPACE_ATTRIBUTES.equals(name) && state) {
                return;
            }
            throw new XmlPullParserException("Unsupported feature: " + name);
        }
        public boolean getFeature(String name) {
            if (FEATURE_PROCESS_NAMESPACES.equals(name)) {
                return true;
            }
            if (FEATURE_REPORT_NAMESPACE_ATTRIBUTES.equals(name)) {
                return true;
            }
            return false;
        }
        public void setProperty(String name, Object value) throws XmlPullParserException {
            throw new XmlPullParserException("setProperty() not supported");
        }
        public Object getProperty(String name) {
            return null;
        }
        public void setInput(Reader in) throws XmlPullParserException {
            throw new XmlPullParserException("setInput() not supported");
        }
        public void setInput(InputStream inputStream, String inputEncoding) throws XmlPullParserException {
            throw new XmlPullParserException("setInput() not supported");
        }
        public void defineEntityReplacementText(String entityName, String replacementText) throws XmlPullParserException {
            throw new XmlPullParserException("defineEntityReplacementText() not supported");
        }
        public String getNamespacePrefix(int pos) throws XmlPullParserException {
            throw new XmlPullParserException("getNamespacePrefix() not supported");
        }
        public String getInputEncoding() {
            return null;
        }
        public String getNamespace(String prefix) {
            throw new RuntimeException("getNamespace() not supported");
        }
        public int getNamespaceCount(int depth) throws XmlPullParserException {
            throw new XmlPullParserException("getNamespaceCount() not supported");
        }
        public String getPositionDescription() {
            return "Binary XML file line #" + getLineNumber();
        }
        public String getNamespaceUri(int pos) throws XmlPullParserException {
            throw new XmlPullParserException("getNamespaceUri() not supported");
        }
        public int getColumnNumber() {
            return -1;
        }
        public int getDepth() {
            return mDepth;
        }
        public String getText() {
            int id = nativeGetText(mParseState);
            return id >= 0 ? mStrings.get(id).toString() : null;
        }
        public int getLineNumber() {
            return nativeGetLineNumber(mParseState);
        }
        public int getEventType() throws XmlPullParserException {
            return mEventType;
        }
        public boolean isWhitespace() throws XmlPullParserException {
            // whitespace was stripped by aapt.
            return false;
        }
        public String getPrefix() {
            throw new RuntimeException("getPrefix not supported");
        }
        public char[] getTextCharacters(int[] holderForStartAndLength) {
            String txt = getText();
            char[] chars = null;
            if (txt != null) {
                holderForStartAndLength[0] = 0;
                holderForStartAndLength[1] = txt.length();
                chars = new char[txt.length()];
                txt.getChars(0, txt.length(), chars, 0);
            }
            return chars;
        }
        public String getNamespace() {
            int id = nativeGetNamespace(mParseState);
            return id >= 0 ? mStrings.get(id).toString() : "";
        }
        public String getName() {
            int id = nativeGetName(mParseState);
            return id >= 0 ? mStrings.get(id).toString() : null;
        }
        public String getAttributeNamespace(int index) {
            int id = nativeGetAttributeNamespace(mParseState, index);
            if (DEBUG) System.out.println("getAttributeNamespace of " + index + " = " + id);
            if (id >= 0) return mStrings.get(id).toString();
            else if (id == -1) return "";
            throw new IndexOutOfBoundsException(String.valueOf(index));
        }
        public String getAttributeName(int index) {
            int id = nativeGetAttributeName(mParseState, index);
            if (DEBUG) System.out.println("getAttributeName of " + index + " = " + id);
            if (id >= 0) return mStrings.get(id).toString();
            throw new IndexOutOfBoundsException(String.valueOf(index));
        }
        public String getAttributePrefix(int index) {
            throw new RuntimeException("getAttributePrefix not supported");
        }
        public boolean isEmptyElementTag() throws XmlPullParserException {
            // XXX Need to detect this.
            return false;
        }
        public int getAttributeCount() {
            return mEventType == START_TAG ? nativeGetAttributeCount(mParseState) : -1;
        }
        public String getAttributeValue(int index) {
            int id = nativeGetAttributeStringValue(mParseState, index);
            if (DEBUG) System.out.println("getAttributeValue of " + index + " = " + id);
            if (id >= 0) return mStrings.get(id).toString();

            // May be some other type...  check and try to convert if so.
            int t = nativeGetAttributeDataType(mParseState, index);
            if (t == TypedValue.TYPE_NULL) {
                throw new IndexOutOfBoundsException(String.valueOf(index));
            }

            int v = nativeGetAttributeData(mParseState, index);
            return TypedValue.coerceToString(t, v);
        }
        public String getAttributeType(int index) {
            return "CDATA";
        }
        public boolean isAttributeDefault(int index) {
            return false;
        }
        public int nextToken() throws XmlPullParserException,IOException {
            return next();
        }
        public String getAttributeValue(String namespace, String name) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, name);
            if (idx >= 0) {
                if (DEBUG) System.out.println("getAttributeName of "
                        + namespace + ":" + name + " index = " + idx);
                if (DEBUG) System.out.println(
                        "Namespace=" + getAttributeNamespace(idx)
                        + "Name=" + getAttributeName(idx)
                        + ", Value=" + getAttributeValue(idx));
                return getAttributeValue(idx);
            }
            return null;
        }
        public int next() throws XmlPullParserException,IOException {
            if (!mStarted) {
                mStarted = true;
                return START_DOCUMENT;
            }
            if (mParseState == 0) {
                return END_DOCUMENT;
            }
            int ev = nativeNext(mParseState);
            if (mDecNextDepth) {
                mDepth--;
                mDecNextDepth = false;
            }
            switch (ev) {
            case START_TAG:
                mDepth++;
                break;
            case END_TAG:
                mDecNextDepth = true;
                break;
            }
            mEventType = ev;
            if (ev == END_DOCUMENT) {
                // Automatically close the parse when we reach the end of
                // a document, since the standard XmlPullParser interface
                // doesn't have such an API so most clients will leave us
                // dangling.
                close();
            }
            return ev;
        }
        public void require(int type, String namespace, String name) throws XmlPullParserException,IOException {
            if (type != getEventType()
                || (namespace != null && !namespace.equals( getNamespace () ) )
                || (name != null && !name.equals( getName() ) ) )
                throw new XmlPullParserException( "expected "+ TYPES[ type ]+getPositionDescription());
        }
        public String nextText() throws XmlPullParserException,IOException {
            if(getEventType() != START_TAG) {
               throw new XmlPullParserException(
                 getPositionDescription()
                 + ": parser must be on START_TAG to read next text", this, null);
            }
            int eventType = next();
            if(eventType == TEXT) {
               String result = getText();
               eventType = next();
               if(eventType != END_TAG) {
                 throw new XmlPullParserException(
                    getPositionDescription()
                    + ": event TEXT it must be immediately followed by END_TAG", this, null);
                }
                return result;
            } else if(eventType == END_TAG) {
               return "";
            } else {
               throw new XmlPullParserException(
                 getPositionDescription()
                 + ": parser must be on START_TAG or TEXT to read text", this, null);
            }
        }
        public int nextTag() throws XmlPullParserException,IOException {
            int eventType = next();
            if(eventType == TEXT && isWhitespace()) {   // skip whitespace
               eventType = next();
            }
            if (eventType != START_TAG && eventType != END_TAG) {
               throw new XmlPullParserException(
                   getPositionDescription() 
                   + ": expected start or end tag", this, null);
            }
            return eventType;
        }
    
        public int getAttributeNameResource(int index) {
            return nativeGetAttributeResource(mParseState, index);
        }
    
        public int getAttributeListValue(String namespace, String attribute,
                String[] options, int defaultValue) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeListValue(idx, options, defaultValue);
            }
            return defaultValue;
        }
        public boolean getAttributeBooleanValue(String namespace, String attribute,
                boolean defaultValue) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeBooleanValue(idx, defaultValue);
            }
            return defaultValue;
        }
        public int getAttributeResourceValue(String namespace, String attribute,
                int defaultValue) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeResourceValue(idx, defaultValue);
            }
            return defaultValue;
        }
        public int getAttributeIntValue(String namespace, String attribute,
                int defaultValue) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeIntValue(idx, defaultValue);
            }
            return defaultValue;
        }
        public int getAttributeUnsignedIntValue(String namespace, String attribute,
                                                int defaultValue)
        {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeUnsignedIntValue(idx, defaultValue);
            }
            return defaultValue;
        }
        public float getAttributeFloatValue(String namespace, String attribute,
                float defaultValue) {
            int idx = nativeGetAttributeIndex(mParseState, namespace, attribute);
            if (idx >= 0) {
                return getAttributeFloatValue(idx, defaultValue);
            }
            return defaultValue;
        }

        public int getAttributeListValue(int idx,
                String[] options, int defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            int v = nativeGetAttributeData(mParseState, idx);
            if (t == TypedValue.TYPE_STRING) {
                return XmlUtils.convertValueToList(
                    mStrings.get(v), options, defaultValue);
            }
            return v;
        }
        public boolean getAttributeBooleanValue(int idx,
                boolean defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            // Note: don't attempt to convert any other types, because
            // we want to count on appt doing the conversion for us.
            if (t >= TypedValue.TYPE_FIRST_INT &&
                t <= TypedValue.TYPE_LAST_INT) {
                return nativeGetAttributeData(mParseState, idx) != 0;
            }
            return defaultValue;
        }
        public int getAttributeResourceValue(int idx, int defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            // Note: don't attempt to convert any other types, because
            // we want to count on appt doing the conversion for us.
            if (t == TypedValue.TYPE_REFERENCE) {
                return nativeGetAttributeData(mParseState, idx);
            }
            return defaultValue;
        }
        public int getAttributeIntValue(int idx, int defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            // Note: don't attempt to convert any other types, because
            // we want to count on appt doing the conversion for us.
            if (t >= TypedValue.TYPE_FIRST_INT &&
                t <= TypedValue.TYPE_LAST_INT) {
                return nativeGetAttributeData(mParseState, idx);
            }
            return defaultValue;
        }
        public int getAttributeUnsignedIntValue(int idx, int defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            // Note: don't attempt to convert any other types, because
            // we want to count on appt doing the conversion for us.
            if (t >= TypedValue.TYPE_FIRST_INT &&
                t <= TypedValue.TYPE_LAST_INT) {
                return nativeGetAttributeData(mParseState, idx);
            }
            return defaultValue;
        }
        public float getAttributeFloatValue(int idx, float defaultValue) {
            int t = nativeGetAttributeDataType(mParseState, idx);
            // Note: don't attempt to convert any other types, because
            // we want to count on appt doing the conversion for us.
            if (t == TypedValue.TYPE_FLOAT) {
                return Float.intBitsToFloat(
                    nativeGetAttributeData(mParseState, idx));
            }
            throw new RuntimeException("not a float!");
        }

        public String getIdAttribute() {
            int id = nativeGetIdAttribute(mParseState);
            return id >= 0 ? mStrings.get(id).toString() : null;
        }
        public String getClassAttribute() {
            int id = nativeGetClassAttribute(mParseState);
            return id >= 0 ? mStrings.get(id).toString() : null;
        }

        public int getIdAttributeResourceValue(int defaultValue) {
            //todo: create and use native method
            return getAttributeResourceValue(null, "id", defaultValue);
        }

        public int getStyleAttribute() {
            return nativeGetStyleAttribute(mParseState);
        }

        public void close() {
            synchronized (mBlock) {
                if (mParseState != 0) {
                    nativeDestroyParseState(mParseState);
                    mParseState = 0;
                    mBlock.decOpenCountLocked();
                }
            }
        }
        
        protected void finalize() throws Throwable {
            close();
        }

        /*package*/ final CharSequence getPooledString(int id) {
            return mStrings.get(id);
        }

        /*package*/ int mParseState;
        private final XmlBlock mBlock;
        private boolean mStarted = false;
        private boolean mDecNextDepth = false;
        private int mDepth = 0;
        private int mEventType = START_DOCUMENT;
    }

    protected void finalize() throws Throwable {
        close();
    }

    /**
     * Create from an existing xml block native object.  This is
     * -extremely- dangerous -- only use it if you absolutely know what you
     *  are doing!  The given native object must exist for the entire lifetime
     *  of this newly creating XmlBlock.
     */
    XmlBlock(AssetManager assets, int xmlBlock) {
        mAssets = assets;
        mNative = xmlBlock;
        mStrings = new StringBlock(nativeGetStringBlock(xmlBlock), false);
    }

    private final AssetManager mAssets;
    private final int mNative;
    private final StringBlock mStrings;
    private boolean mOpen = true;
    private int mOpenCount = 1;

    private static final native int nativeCreate(byte[] data,
                                                 int offset,
                                                 int size);
    private static final native int nativeGetStringBlock(int obj);

    private static final native int nativeCreateParseState(int obj);
    private static final native int nativeNext(int state);
    private static final native int nativeGetNamespace(int state);
    private static final native int nativeGetName(int state);
    private static final native int nativeGetText(int state);
    private static final native int nativeGetLineNumber(int state);
    private static final native int nativeGetAttributeCount(int state);
    private static final native int nativeGetAttributeNamespace(int state, int idx);
    private static final native int nativeGetAttributeName(int state, int idx);
    private static final native int nativeGetAttributeResource(int state, int idx);
    private static final native int nativeGetAttributeDataType(int state, int idx);
    private static final native int nativeGetAttributeData(int state, int idx);
    private static final native int nativeGetAttributeStringValue(int state, int idx);
    private static final native int nativeGetIdAttribute(int state);
    private static final native int nativeGetClassAttribute(int state);
    private static final native int nativeGetStyleAttribute(int state);
    private static final native int nativeGetAttributeIndex(int state, String namespace, String name);
    private static final native void nativeDestroyParseState(int state);

    private static final native void nativeDestroy(int obj);
}