KEMBAR78
QSpiders - Memory (JVM architecture) | PPTX
JVM architecture
By,
Vikas S Kumar
Software Engineer
JVM architecture
What is class file……?
• When the .java files are compiled we get .class files, these
are called as class file
• [.class file is also called as byte code]
• Our JVM can understand only .class file (or byte code)
• [Byte-code will also increase the security in java]
• For each class in a file there will be separate .class file
• The class loader loads the .class file into memory
What class loader does….?
• The class loader loads the class into memory
[.class]
• The classes are loaded into memory when the
call is made to any of his members
• [Class members are - methods(static or instance)
, constructors, variables(static or instance)]
• Method area
– It is the place were all the methods are saved.
– All instance methods are stored in this area
– Methods are taken from this region to execute
• Stack region
– It is one of the major part of memory
– It is the place were the method execution takes place
– Methods gets executed in the method block present in
stack region
– All the local members are stored in this region
• Heap area
– Heap is also one of the major part of memory
– It is the place all the objects of the class are stored
– It contains String pool and static pool
– String objects are stored in string pool
– All static members are stored in static pool
• PC-register
– It is a register memory
– It is used to store the information about the next instruction
which need to be executed
– Such that it keep a track each instruction which need to be
executed
• Native method area
– It is the place where the native programming language
code is stored.
– The native programming language code might be like
C, CPP, C# etc
– To execute these code we need the help of Native
method library, were our JVm take help of this library

QSpiders - Memory (JVM architecture)

  • 1.
    JVM architecture By, Vikas SKumar Software Engineer
  • 2.
  • 3.
    What is classfile……? • When the .java files are compiled we get .class files, these are called as class file • [.class file is also called as byte code] • Our JVM can understand only .class file (or byte code) • [Byte-code will also increase the security in java] • For each class in a file there will be separate .class file • The class loader loads the .class file into memory
  • 4.
    What class loaderdoes….? • The class loader loads the class into memory [.class] • The classes are loaded into memory when the call is made to any of his members • [Class members are - methods(static or instance) , constructors, variables(static or instance)]
  • 5.
    • Method area –It is the place were all the methods are saved. – All instance methods are stored in this area – Methods are taken from this region to execute • Stack region – It is one of the major part of memory – It is the place were the method execution takes place – Methods gets executed in the method block present in stack region – All the local members are stored in this region
  • 6.
    • Heap area –Heap is also one of the major part of memory – It is the place all the objects of the class are stored – It contains String pool and static pool – String objects are stored in string pool – All static members are stored in static pool • PC-register – It is a register memory – It is used to store the information about the next instruction which need to be executed – Such that it keep a track each instruction which need to be executed
  • 7.
    • Native methodarea – It is the place where the native programming language code is stored. – The native programming language code might be like C, CPP, C# etc – To execute these code we need the help of Native method library, were our JVm take help of this library

Editor's Notes

  • #2 The Agenda (Intermediate)   To reproduce the shape effects on this slide, do the following: On the Home tab, in the Slides group, click Layout, and then click Blank. On the Insert tab, in the Illustrations group, click Shapes, and then under Block Arrows select Chevron (under Block Arrows, second row, eighth option from left). On the slide, drag to draw a chevron arrow. Under Drawing Tools, on the Format tab, in the Size group, click the arrow at the bottom right corner launching the Format Shape dialog box. In the Format Shape dialog box, select Size in the left pane, under Size and Rotate in the right pane set the Height to 1.35” and the Width to 8.65”. Also in the Format Shape dialog box, select Position in the left pane, under Position on Slide in the right pane set the Horizontal to .61” and the Vertical to 1.36”. Also in the Format Shape dialog box, select Text Box in the left pane, under Text Layout in the right pane set the Vertical Alignment to Middle, under Autofit, select Do not Autofit, and then under Internal Margin set the Left to 1.4” and the Right to 0.1”. Also in the Format Shape dialog box, select Fill in the left pane, under Fill in the right pane select Gradient Fill. Under Gradient stops, click Add gradient stop or Remove gradient stop until four stops appear on the slider. Customize the gradient stops as follows: Select the first stop on the slider, and then do the following: In the Position box, enter 0%. Click the button next to Color, and then under Theme Colors select Dark Blue, Text 2, Lighter 40% (fourth row, fourth option from the left). Select the second stop on the list, and then do the following: In the Position box, enter 48%. Click the button next to Color, and then under Theme Colors select Dark Blue, Text 2, Lighter 60% (third row, fourth option from the left). Select the third stop on the slider, and then do the following: In the Position box, enter 61%. Click the button next to Color, and then under Theme Colors select Dark Blue, Text 2, Lighter 60% (third row, fourth option from the left). Select the last stop on the list, and then do the following: In the Position box, enter 100%. Click the button next to Color, and then under Theme Colors select Dark Blue, Text 2, Lighter 40% (fourth row, fourth option from the left). Also in the Format Shape dialog box, select Line Color in the left pane, under Line Color in the right pane select No Line. Also in the Format Shape dialog box, select Shadow in the left pane, under Shadow in the right pane click the arrow to the right of Color and under Theme Colors select, Black, Text 1 (first row, second option from left), and then do the following: In the Transparency box, enter 60%. In the Size box, enter 100%. In the Blur box, enter 10 pt. In the Angle box, enter 90 degrees. In the Distance box, enter 3 pt. Close Format Shape dialog box. Type “Topic 1” in the shape, then select the text. On the Home tab, in the Font group, select Segoe UI Semibold from the Font list, and then select 36 pt from the Font Size list. Also on the Home tab, in the Font group, click the Text Shadow icon. Also on the Home tab, in the Font group, click the arrow next to Font Color and under Theme Colors select White, Background 1 (first row, first option from left). Select the chevron shape. On the Home tab, in the Clipboard group, click Copy, then select Duplicate. Repeat this step one more time, creating three shapes total. Select the third duplicated shape. Under Drawing Tools, on the Format tab, in the Size group, click the arrow at the bottom right corner launching the Format Shape dialog box. In the Format Shape dialog box, select Position in the left pane, under Position on slide in the right pane set the Horizontal to .57” and the Vertical to 4.61”. Press and hold CTRL, and select all three shapes. On the Home tab, in the Drawing group, click Arrange, point to Align and then to the following: Click Align Left. Click Distribute Vertically. Select text in the second chevron and change text to “Topic 2”. Select text in third chevron and change text to “Topic 3”.   To reproduce the video effects on this slide, do the following: On the Insert tab, in the Media group, click Video, and then click Video from File. In the left pane of the Insert Video dialog box, click the drive or library that contains the video. In the right pane of the dialog box, click the video that you want and then click Insert. Under Video Tools, on the Format tab, in the Video Styles group, click Video Shape, and under Block Arrows select Chevron. (second row, eighth option from left). Also under Video Tools, on the Format tab, in the Video Styles group, click the arrow at the bottom right corner, launching the Format Video dialog box. In the Format Video dialog box, select Size in the left pane, under Size and Rotate in the right pane set the Height to 1.3” and the Width to 1.71”. Also in the Format Video dialog box, select Border Color in the left pane, under Border Color in the right pane, select Solid Line. Click the button next to Color, and then under Theme Colors select Dark Blue, Text 2, Lighter 40% (fourth row, fourth option from the left). Also in the Format Video dialog box, select Border Style in the left pane, under Border Style in the right pane set the Width to 3 pt. Also in the Format Video dialog box, select Shadow in the left pane, under Shadow in the right pane click the arrow to the right of Presets and under Outer, select Offset Right (second row, first option from left). Also in the Format Video dialog box, select 3-D Format in the left pane, under Bevel in the right pane click the arrow to the right of Top and under Bevel, select Riblet (third row, second option from left), then set the Width as 8 pt and the Height as 6 pt, and then under Surface, click the arrow to the right of Material and select Warm Matte (first row, second option from left). On the Animations tab, in the Animation group, select Play. Also on the Animations tab in the Timing group, click the arrow to the right of Start and select With Previous. With the video still selected, under Video Tools, on the Playback tab, in the Video Options group, select Loop Until Stopped. Press and hold CTRL, select video and first shape. On the Home tab, in the Drawing group, click Arrange, point to Align and then to the following: Click Align Left. Click Align Middle. Select the video. On the Home tab, in the Clipboard group, click the arrow to the right of Copy, and then click Duplicate. Repeat this process once more for a total of three videos. Press and hold CTRL, select the last video and bottom shape. On the Home tab, in the Drawing group, click Arrange, point to Align and then to the following: Click Align Left. Click Align Middle. Press and hold CTRL, select the second video and middle shape. On the Home tab, in the Drawing group, click Arrange, point to Align and then to the following: Click Align Left. Click Align Middle.   To reproduce the background effects on this slide, do the following: On the Design tab, in the bottom right corner of the Background group, click the arrow at the bottom right launching the Format Background dialog box. In the Format Background dialog box, select Fill in the left pane, under Fill in the right pane select Gradient Fill. Under Gradient stops, click Add gradient stop or Remove gradient stop until three stops appear on the slider. Customize the gradient stops as follows: Select the first stop on the slider, and then do the following: In the Position box, enter 0%. Click the button next to Color, and then under Theme Colors select White, Background 1 (first row, first option from the left). Select the second stop on the list, and then do the following: In the Position box, enter 50%. Click the button next to Color, and then under Theme Colors select Blue Accent 1, Lighter 60% (third row, fifth option from the left). Select the last stop on the slider, and then do the following: In the Position box, enter 100%. Click the button next to Color, and then under Theme Colors select White, Background 1 (first row, first option from the left). On the Insert tab, in the Images group, click Picture. In the left pane of the Insert Picture dialog box, click the drive or library that contains the picture. In the right pane of the dialog box, click the pictures that you want and then click Insert. With the picture selected, under Picture Tools, on the Format tab, in the Size group, set the Width to 10”. On the Home tab, in the Drawing group, click Arrange, point to Align, and then do the following: Click Align Center. Click Align Bottom. With the picture still selected, on the Home tab, in the Clipboard group, click the arrow to the right of Copy, and then click Duplicate. With the new picture selected, on the Home tab, in the Drawing group, click Arrange, point to Rotate, and select Flip Vertical. Also on the Home tab, in the Drawing group, click Arrange, point to Align, and then do the following: Click Align Center. Click Align Top. Press CTRL and select both of the pictures. On the Home tab, in the Drawing group, click Arrange, under Order Objects, click Send to Back.